BiochemistryFrom Wikipedia, the free encyclopedia

Jump to: navigation, searchFor the journal, see Biochemistry (journal)."Biological Chemistry" redirects here. For the journal formerly named Biological Chemistry Hoppe-Seyler, see Biological Chemistry (journal).

Biochemistry is the study of the chemical processes in living organisms. It deals with the structures and functions of cellular components such as proteins, carbohydrates, lipids, nucleic acids and other biomolecules.

Among the vast number of different biomolecules, many are complex and large molecules (called polymers), which are composed of similar repeating subunits (called monomers). Each class of polymeric biomolecule has a different set of subunit types.[1] For example, a protein is a polymer whose subunits are selected from a set of 20 or more amino acids. Biochemistry studies the chemical properties of important biological molecules, like proteins, and in particular the chemistry of enzyme-catalyzed reactions.

The biochemistry of cell metabolism and the endocrine system has been extensively described. Other areas of biochemistry include the genetic code (DNA, RNA), protein synthesis, cell membrane transport, and signal transduction.

Contents

[hide]

1 History 2 Monomers and Polymers

o 2.1 Carbohydrates o 2.2 Lipids o 2.3 Proteins o 2.4 Nucleic Acids

3 Carbohydrates o 3.1 Monosaccharides o 3.2 Disaccharides o 3.3 Oligosaccharides and polysaccharides o 3.4 Use of carbohydrates as an energy source

3.4.1 Glycolysis (anaerobic) 3.4.2 Aerobic 3.4.3 Gluconeogenesis

4 Proteins 5 Lipids

6 Nucleic acids 7 Relationship to other "molecular-scale" biological sciences 8 See also

o 8.1 Lists o 8.2 Related topics

9 References 10 Further reading 11 External links

[edit] History

Main article: History of biochemistry

Originally, it was generally believed that life was not subject to the laws of science the way non-life was. It was thought that only living beings could produce the molecules of life (from other, previously existing biomolecules). Then, in 1828, Friedrich Wöhler published a paper on the synthesis of urea, proving that organic compounds can be created artificially.[2][3]

The dawn of biochemistry may have been the discovery of the first enzyme, diastase (today called amylase), in 1833 by Anselme Payen. Eduard Buchner contributed the first demonstration of a complex biochemical process outside of a cell in 1896: alcoholic fermentation in cell extracts of yeast. Although the term “biochemistry” seems to have been first used in 1882, it is generally accepted that the formal coinage of biochemistry occurred in 1903 by Carl Neuberg, a German chemist. Previously, this area would have been referred to as physiological chemistry. Since then, biochemistry has advanced, especially since the mid-20th century, with the development of new techniques such as chromatography, X-ray diffraction, dual polarisation interferometry, NMR spectroscopy, radioisotopic labeling, electron microscopy and molecular dynamics simulations. These techniques allowed for the discovery and detailed analysis of many molecules and metabolic pathways of the cell, such as glycolysis and the Krebs cycle (citric acid cycle).

Another significant historic event in biochemistry is the discovery of the gene and its role in the transfer of information in the cell. This part of biochemistry is often called molecular biology. In the 1950s, James D. Watson, Francis Crick, Rosalind Franklin, and Maurice Wilkins were instrumental in solving DNA structure and suggesting its relationship with genetic transfer of information. In 1958, George Beadle and Edward Tatum received the Nobel Prize for work in fungi showing that one gene produces one enzyme. In 1988, Colin Pitchfork was the first person convicted of murder with DNA evidence, which led to growth of forensic science. More recently, Andrew Z. Fire and Craig C. Mello received the 2006 Nobel Prize for discovering the role of RNA interference (RNAi), in the silencing of gene expression

Today, there are three main types of biochemistry. Plant biochemistry involves the study of the biochemistry of autotrophic organisms such as photosynthesis and other plant specific biochemical processes. General biochemistry encompasses both plant and animal biochemistry.

Human/medical/medicinal biochemistry focuses on the biochemistry of humans and medical illnesses.[citation needed]

[edit] Monomers and Polymers

Main articles: Monomer and Polymer

Monomers and polymers are a structural basis in which the four main macromolecules (carbohydrates, lipids, proteins, and nucleic acids), or biopolymers, of biochemistry are based on. Monomers are smaller micromolecules that are put together to make macromolecules. Polymers are those macromolecules that are created when monomers are synthesized together. When they are synthesized, the two molecules undergo a process called dehydration synthesis.

[edit] Carbohydrates

Main articles: Carbohydrates, Monosaccharides, Disaccharides, and Polysaccharides

A molecule of sucrose (glucose + fructose), a disaccharide.

Carbohydrates have monomers called monosaccharides. Some of these monosaccharides include glucose (C6H12O6), fructose (C6H12O6), and deoxyribose (C5H10O4). When two monosaccharides undergo dehydration synthesis, water is produced, as two hydrogen atoms and one oxygen atom are lost from the two monosaccharides' hydroxyl group.

[edit] Lipids

Main articles: Lipids, Glycerol, and Fatty acids

A triglyceride with a glycerol molecule on the left and three fatty acids coming off it.

Lipids are usually made up of a molecule of glycerol and other molecules. In triglycerides, or the main lipid, there is one molecule of glycerol, and three fatty acids. Fatty acids are considered the monomer in that case, and could be saturated (no double bonds in the carbon chain) or unsaturated (one or more double bond in the carbon chain). Lipids, especially phospholipids, are also used in different pharmaceutical products, either as co-solubilisers e.g. in Parenteral infusions or else as drug carrier components (e.g. in a Liposome or Transfersome).

[edit] Proteins

Main articles: Proteins and Amino Acids

The general structure of an α-amino acid, with the amino group on the left and the carboxyl group on the right.

Proteins are macro biopolymers, and have monomers of amino acids. There are 20 standard amino acids, and they contain a carboxyl group, an amino group, and a side chain (or an "R" group). The "R" group is what makes each amino acid different, and the properties of the side chains greatly influence the overall three-dimensional confirmation of a protein. When Amino acids combine, they form a special bond called a peptide bond through dehydration synthesis, and become a polypeptide, or a protein.

[edit] Nucleic Acids

Main articles: Nucleic acid, DNA, RNA, and Nucleotides

The structure of deoxyribonucleic acid (DNA), the picture shows the monomers being put together.

Nucleic acids are very important in biochemistry, as they are what make up DNA, something all cellular organism use to store their genetic information. The most common nucleic acids are deoxyribonucleic acid and ribonucleic acid. Their monomers are called nucleotides. The most common nucleotides are called adenine, cytosine, guanine, thymine, and uracil. Adenine binds with thymine and uracil, thymine only binds with adenine. Cytosine and guanine can only bind with each other.

[edit] Carbohydrates

Main article: Carbohydrate

The function of carbohydrates includes energy storage and providing structure. Sugars are carbohydrates, but not all carbohydrates are sugars. There are more carbohydrates on Earth than any other known type of biomolecule; they are used to store energy and genetic information, as well as play important roles in cell to cell interactions and communications.

[edit] Monosaccharides

Glucose

The simplest type of carbohydrate is a monosaccharide, which among other properties contains carbon, hydrogen, and oxygen, mostly in a ratio of 1:2:1 (generalized formula CnH2nOn, where n is at least 3). Glucose, one of the most important carbohydrates, is an example of a monosaccharide. So is fructose, the sugar that gives fruits their sweet taste. Some carbohydrates (especially after condensation to oligo- and polysaccharides) contain less carbon relative to H and O, which still are present in 2:1 (H:O) ratio. Monosaccharides can be grouped into aldoses (having an aldehyde group at the end of the chain, e. g. glucose) and ketoses (having a keto group in their chain; e. g. fructose). Both aldoses and ketoses occur in an equilibrium between the open-chain forms and (starting with chain lengths of C4) cyclic forms. These are generated by bond formation between one of the hydroxyl groups of the sugar chain with the carbon of the aldehyde or keto group to form a hemiacetal bond. This leads to saturated five-membered (in furanoses) or six-membered (in pyranoses) heterocyclic rings containing one O as heteroatom.

[edit] Disaccharides

Sucrose: ordinary table sugar and probably the most familiar carbohydrate.

Two monosaccharides can be joined together using dehydration synthesis, in which a hydrogen atom is removed from the end of one molecule and a hydroxyl group (—OH) is removed from the other; the remaining residues are then attached at the sites from which the atoms were removed. The H—OH or H2O is then released as a molecule of water, hence the term dehydration. The new molecule, consisting of two monosaccharides, is called a disaccharide and is conjoined together by a glycosidic or ether bond. The reverse reaction can also occur, using a

molecule of water to split up a disaccharide and break the glycosidic bond; this is termed hydrolysis. The most well-known disaccharide is sucrose, ordinary sugar (in scientific contexts, called table sugar or cane sugar to differentiate it from other sugars). Sucrose consists of a glucose molecule and a fructose molecule joined together. Another important disaccharide is lactose, consisting of a glucose molecule and a galactose molecule. As most humans age, the production of lactase, the enzyme that hydrolyzes lactose back into glucose and galactose, typically decreases. This results in lactase deficiency, also called lactose intolerance.

Sugar polymers are characterised by having reducing or non-reducing ends. A reducing end of a carbohydrate is a carbon atom which can be in equilibrium with the open-chain aldehyde or keto form. If the joining of monomers takes place at such a carbon atom, the free hydroxy group of the pyranose or furanose form is exchanged with an OH-side chain of another sugar, yielding a full acetal. This prevents opening of the chain to the aldehyde or keto form and renders the modified residue non-reducing. Lactose contains a reducing end at its glucose moiety, whereas the galactose moiety form a full acetal with the C4-OH group of glucose. Saccharose does not have a reducing end because of full acetal formation between the aldehyde carbon of glucose (C1) and the keto carbon of fructose (C2).

[edit] Oligosaccharides and polysaccharides

Cellulose as polymer of β-D-glucose

When a few (around three to six) monosaccharides are joined together, it is called an oligosaccharide (oligo- meaning "few"). These molecules tend to be used as markers and signals, as well as having some other uses. Many monosaccharides joined together make a polysaccharide. They can be joined together in one long linear chain, or they may be branched. Two of the most common polysaccharides are cellulose and glycogen, both consisting of repeating glucose monomers.

Cellulose is made by plants and is an important structural component of their cell walls. Humans can neither manufacture nor digest it.

Glycogen, on the other hand, is an animal carbohydrate; humans and other animals use it as a form of energy storage.

[edit] Use of carbohydrates as an energy source

See also carbohydrate metabolism

Glucose is the major energy source in most life forms. For instance, polysaccharides are broken down into their monomers (glycogen phosphorylase removes glucose residues from glycogen). Disaccharides like lactose or sucrose are cleaved into their two component monosaccharides.

[edit] Glycolysis (anaerobic)

Glucose is mainly metabolized by a very important ten-step pathway called glycolysis, the net result of which is to break down one molecule of glucose into two molecules of pyruvate; this also produces a net two molecules of ATP, the energy currency of cells, along with two reducing equivalents in the form of converting NAD + to NADH. This does not require oxygen; if no oxygen is available (or the cell cannot use oxygen), the NAD is restored by converting the pyruvate to lactate (lactic acid) (e. g. in humans) or to ethanol plus carbon dioxide (e. g. in yeast). Other monosaccharides like galactose and fructose can be converted into intermediates of the glycolytic pathway.

[edit] Aerobic

In aerobic cells with sufficient oxygen, like most human cells, the pyruvate is further metabolized. It is irreversibly converted to acetyl-CoA, giving off one carbon atom as the waste product carbon dioxide, generating another reducing equivalent as NADH. The two molecules acetyl-CoA (from one molecule of glucose) then enter the citric acid cycle, producing two more molecules of ATP, six more NADH molecules and two reduced (ubi)quinones (via FADH2 as enzyme-bound cofactor), and releasing the remaining carbon atoms as carbon dioxide. The produced NADH and quinol molecules then feed into the enzyme complexes of the respiratory chain, an electron transport system transferring the electrons ultimately to oxygen and conserving the released energy in the form of a proton gradient over a membrane (inner mitochondrial membrane in eukaryotes). Thereby, oxygen is reduced to water and the original electron acceptors NAD+ and quinone are regenerated. This is why humans breathe in oxygen and breathe out carbon dioxide. The energy released from transferring the electrons from high-energy states in NADH and quinol is conserved first as proton gradient and converted to ATP via ATP synthase. This generates an additional 28 molecules of ATP (24 from the 8 NADH + 4 from the 2 quinols), totaling to 32 molecules of ATP conserved per degraded glucose (two from glycolysis + two from the citrate cycle). It is clear that using oxygen to completely oxidize glucose provides an organism with far more energy than any oxygen-independent metabolic feature, and this is thought to be the reason why complex life appeared only after Earth's atmosphere accumulated large amounts of oxygen.

[edit] Gluconeogenesis

Main article: Gluconeogenesis

In vertebrates, vigorously contracting skeletal muscles (during weightlifting or sprinting, for example) do not receive enough oxygen to meet the energy demand, and so they shift to anaerobic metabolism, converting glucose to lactate. The liver regenerates the glucose, using a process called gluconeogenesis. This process is not quite the opposite of glycolysis, and actually requires three times the amount of energy gained from glycolysis (six molecules of ATP are

used, compared to the two gained in glycolysis). Analogous to the above reactions, the glucose produced can then undergo glycolysis in tissues that need energy, be stored as glycogen (or starch in plants), or be converted to other monosaccharides or joined into di- or oligosaccharides. The combined pathways of glycolysis during exercise, lactate's crossing via the bloodstream to the liver, subsequent gluconeogenesis and release of glucose into the bloodstream is called the Cori cycle.[citation needed]

[edit] Proteins

Main article: Protein

A schematic of hemoglobin. The red and blue ribbons represent the protein globin; the green structures are the heme groups.

Like carbohydrates, some proteins perform largely structural roles. For instance, movements of the proteins actin and myosin ultimately are responsible for the contraction of skeletal muscle. One property many proteins have is that they specifically bind to a certain molecule or class of molecules—they may be extremely selective in what they bind. Antibodies are an example of proteins that attach to one specific type of molecule. In fact, the enzyme-linked immunosorbent assay (ELISA), which uses antibodies, is currently one of the most sensitive tests modern medicine uses to detect various biomolecules. Probably the most important proteins, however, are the enzymes. These molecules recognize specific reactant molecules called substrates; they then catalyze the reaction between them. By lowering the activation energy, the enzyme speeds up that reaction by a rate of 1011 or more: a reaction that would normally take over 3,000 years to complete spontaneously might take less than a second with an enzyme. The enzyme itself is not used up in the process, and is free to catalyze the same reaction with a new set of substrates. Using various modifiers, the activity of the enzyme can be regulated, enabling control of the biochemistry of the cell as a whole.

In essence, proteins are chains of amino acids. An amino acid consists of a carbon atom bound to four groups. One is an amino group, —NH2, and one is a carboxylic acid group, —COOH (although these exist as —NH3

+ and —COO− under physiologic conditions). The third is a simple hydrogen atom. The fourth is commonly denoted "—R" and is different for each amino acid. There are twenty standard amino acids. Some of these have functions by themselves or in a modified form; for instance, glutamate functions as an important neurotransmitter.

Generic amino acids (1) in neutral form, (2) as they exist physiologically, and (3) joined together as a dipeptide.

Amino acids can be joined together via a peptide bond. In this dehydration synthesis, a water molecule is removed and the peptide bond connects the nitrogen of one amino acid's amino group to the carbon of the other's carboxylic acid group. The resulting molecule is called a dipeptide, and short stretches of amino acids (usually, fewer than around thirty) are called peptides or polypeptides. Longer stretches merit the title proteins. As an example, the important blood serum protein albumin contains 585 amino acid residues.

The structure of proteins is traditionally described in a hierarchy of four levels. The primary structure of a protein simply consists of its linear sequence of amino acids; for instance, "alanine-glycine-tryptophan-serine-glutamate-asparagine-glycine-lysine-…". Secondary structure is concerned with local morphology. Some combinations of amino acids will tend to curl up in a coil called an α-helix or into a sheet called a β-sheet; some α-helixes can be seen in the hemoglobin schematic above. Tertiary structure is the entire three-dimensional shape of the protein. This shape is determined by the sequence of amino acids. In fact, a single change can change the entire structure. The alpha chain of hemoglobin contains 146 amino acid residues; substitution of the glutamate residue at position 6 with a valine residue changes the behavior of hemoglobin so much that it results in sickle-cell disease. Finally quaternary structure is concerned with the structure of a protein with multiple peptide subunits, like hemoglobin with its four subunits. Not all proteins have more than one subunit.

Ingested proteins are usually broken up into single amino acids or dipeptides in the small intestine, and then absorbed. They can then be joined together to make new proteins. Intermediate products of glycolysis, the citric acid cycle, and the pentose phosphate pathway can be used to make all twenty amino acids, and most bacteria and plants possess all the necessary enzymes to synthesize them. Humans and other mammals, however, can only synthesize half of them. They cannot synthesize isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. These are the essential amino acids, since it is essential to ingest them. Mammals do possess the enzymes to synthesize alanine, asparagine, aspartate, cysteine, glutamate, glutamine, glycine, proline, serine, and tyrosine, the nonessential amino acids. While they can synthesize arginine and histidine, they cannot produce it in sufficient amounts for young, growing animals, and so these are often considered essential amino acids.

If the amino group is removed from an amino acid, it leaves behind a carbon skeleton called an α-keto acid. Enzymes called transaminases can easily transfer the amino group from one amino acid (making it an α-keto acid) to another α-keto acid (making it an amino acid). This is important in the biosynthesis of amino acids, as for many of the pathways, intermediates from other biochemical pathways are converted to the α-keto acid skeleton, and then an amino group

is added, often via transamination. The amino acids may then be linked together to make a protein.

A similar process is used to break down proteins. It is first hydrolyzed into its component amino acids. Free ammonia (NH3), existing as the ammonium ion (NH4

+) in blood, is toxic to life forms. A suitable method for excreting it must therefore exist. Different strategies have evolved in different animals, depending on the animals' needs. Unicellular organisms, of course, simply release the ammonia into the environment. Similarly, bony fish can release the ammonia into the water where it is quickly diluted. In general, mammals convert the ammonia into urea, via the urea cycle.

[edit] Lipids

Main article: Lipid

The term lipid comprises a diverse range of molecules and to some extent is a catchall for relatively water-insoluble or nonpolar compounds of biological origin, including waxes, fatty acids, fatty-acid derived phospholipids, sphingolipids, glycolipids and terpenoids (e.g. retinoids and steroids). Some lipids are linear aliphatic molecules, while others have ring structures. Some are aromatic, while others are not. Some are flexible, while others are rigid.

Most lipids have some polar character in addition to being largely nonpolar. Generally, the bulk of their structure is nonpolar or hydrophobic ("water-fearing"), meaning that it does not interact well with polar solvents like water. Another part of their structure is polar or hydrophilic ("water-loving") and will tend to associate with polar solvents like water. This makes them amphiphilic molecules (having both hydrophobic and hydrophilic portions). In the case of cholesterol, the polar group is a mere -OH (hydroxyl or alcohol). In the case of phospholipids, the polar groups are considerably larger and more polar, as described below.

Lipids are an integral part of our daily diet. Most oils and milk products that we use for cooking and eating like butter, cheese, ghee etc, are composed of fats. Vegetable oils are rich in various polyunsaturated fatty acids (PUFA). Lipid-containing foods undergo digestion within the body and are broken into fatty acids and glycerol, which are the final degradation products of fats and lipids.

[edit] Nucleic acids

Main article: Nucleic acid

A nucleic acid is a complex, high-molecular-weight biochemical macromolecule composed of nucleotide chains that convey genetic information. The most common nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Nucleic acids are found in all living cells and viruses. Aside from the genetic material of the cell, nucleic acids often play a role as second messengers, as well as forming the base molecule for adenosine triphosphate, the primary energy-carrier molecule found in all living organisms.

Nucleic acid, so called because of its prevalence in cellular nuclei, is the generic name of the family of biopolymers. The monomers are called nucleotides, and each consists of three components: a nitrogenous heterocyclic base (either a purine or a pyrimidine), a pentose sugar, and a phosphate group. Different nucleic acid types differ in the specific sugar found in their chain (e.g. DNA or deoxyribonucleic acid contains 2-deoxyriboses). Also, the nitrogenous bases possible in the two nucleic acids are different: adenine, cytosine, and guanine occur in both RNA and DNA, while thymine occurs only in DNA and uracil occurs in RNA.

[edit] Relationship to other "molecular-scale" biological sciences

Schematic relationship between biochemistry, genetics and molecular biology

Researchers in biochemistry use specific techniques native to biochemistry, but increasingly combine these with techniques and ideas from genetics, molecular biology and biophysics. There has never been a hard-line between these disciplines in terms of content and technique. Today the terms molecular biology and biochemistry are nearly interchangeable. The following figure is a schematic that depicts one possible view of the relationship between the fields:

Simplistic overview of the chemical basis of love, one of many applications that may be described in terms of biochemistry.

Biochemistry is the study of the chemical substances and vital processes occurring in living organisms. Biochemists focus heavily on the role, function, and structure of biomolecules. The study of the chemistry behind biological processes and the synthesis of biologically active molecules are examples of biochemistry.

Genetics is the study of the effect of genetic differences on organisms. Often this can be inferred by the absence of a normal component (e.g. one gene). The study of "mutants" – organisms which lack one or more functional components with respect to the so-called "wild type" or normal phenotype. Genetic interactions (epistasis) can often confound simple interpretations of such "knock-out" studies.

Molecular biology is the study of molecular underpinnings of the process of replication, transcription and translation of the genetic material. The central dogma of molecular biology where genetic material is transcribed into RNA and then translated into protein, despite being an oversimplified picture of molecular biology, still provides a good starting point for understanding the field. This picture, however, is undergoing revision in light of emerging novel roles for RNA.

Chemical Biology seeks to develop new tools based on small molecules that allow minimal perturbation of biological systems while providing detailed information about their function. Further, chemical biology employs biological systems to create non-natural hybrids between biomolecules and synthetic devices (for example emptied viral capsids that can deliver gene therapy or drug molecules).

List of biochemistsFrom Wikipedia, the free encyclopedia

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Articles about famous biochemists include:

Contents: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z    See also 

[edit] A

Isaac Asimov , (1920-1992), Russian-born American, prolific author of popular science, as well as science-fiction.

John E. Amoore , British, Biochemist who postulated the stereochemical theory of olfaction in 1952.

William Astbury , (1898-1961), British, pioneer in applying X-ray crystallography to biological molecules such as proteins

[edit] B

Konrad Emil Bloch , (1912-2000), German-American, 1964 Nobel Prize in Physiology or Medicine

Paul D. Boyer , (born 1918), American, studies on ATP synthase, won the Nobel prize for chemistry in 1997

Adrian John Brown , (1852-1920), British, pioneer in enzyme kinetics Eduard Buchner , (1860-1917), German, 1907 Nobel Prize in Chemistry see fermentation

(biochemistry) Boris Pavlovich Belousov (1893 - 1970), USSR, chemist/biophysicist, Belousov-

Zhabotinsky reaction.

[edit] C

Carl Ferdinand Cori , (1896-1984), American, 1947 Nobel Prize in Physiology or Medicine, glycogen research.

Robert Corey , (1897 – 1971), American, co-discoverer of the alpha helix and beta sheet Gerty Cori , (1896-1957), American, 1947 Nobel Prize in Physiology or Medicine,

glycogen research. Peter Coveney , UK, Computational molecular biology specialist. Robert K. Crane , (born 1919), American, discovered sodium-glucose cotransport. Francis Crick , (1916-2004), British, discovered the double helical structure of DNA.

[edit] D

Carl Peter Henrik Dam (1895-1976), Danish, 1943 Nobel Prize in Physiology or Medicine

Revaz Dogonadze (1931-1985), Georgian, Co-author of the quantum-mechanical model of Enzyme Catalysis

Jack Cecil Drummond FRS (1891-1952), isolation of Vitamin A, wartime advisor on nutrition

Christian de Duve , (born 1917), British-born Belgian, 1974 Nobel Prize for Physiology or Medicine

[edit] E

Akira Endo , statins

[edit] F

Heinz Fraenkel-Conrat , (1910-1999), Polish, virus research. Rosalind Franklin , (1920-1958), X-ray crystallographer who helped determine the

structure of DNA Kazimierz Funk , (1884-1967), Polish, see Vitamin

[edit] G

Merrill Garnett , (born 1930), American biochemist David E. Green , (1910 - 1983) pioneer in the study of enzymes, particularly those

involved in oxidative phosphorylation. Frederick Griffith , (1879 - 1941), British, discovered that DNA carried hereditary

information. Walter Gilbert , (born 1932), American, 1980 Nobel Prize in Chemistry, molecular

biologist, see also Biogen Duane Gish , (???), ???, see Institute for Creation Research.

[edit] H

John Scott Haldane , (1860-1936), British, physiologist. Dorothy Hodgkin , (1910-1994), British, founder of protein crystallography and Nobel

Prize winner Frederick Gowland Hopkins , (1861-1947), British, Nobel Prize-winner for the discovery

of vitamins Arthur Harden , (1865-1940), British, awarded a Nobel prize for studies on the enzymes

of fermentation Wayne L. Hubbell , (born 1943), American, biochemist-pioneer of site-directed spin

labeling Max Henius , (1859 - 1935) Danish-American Biochemist who specialized in the

fermentation processes.

[edit] I

[edit] J

[edit] K

Herman Kalckar , (1908-1991), Danish, early work on cellular respiration, nucleotide metabolism and galactose metabolism.

Sir Bernard Katz (1911-2003), German-born, 1970 Nobel Prize in physiology or medicine for work on nerve biochemistry and the pineal gland.

Stuart Alan Kauffman , (born 1939), ???, John Kendrew , (1917-1997), British. Nobel Prize in Chemistry in 1962 for determining

the first crystal structure of a protein, myoglobin. Sir Ernest Kennaway, (1881–1958), British. Early work on carcinogenic effects of

hydrocarbons Arthur Kornberg , (1918-2007) American biochemist, won the Nobel Prize in 1959 for

discovery of DNA polymerase. Sir Hans Kornberg, (born 1928), British. Microbial biochemistry Roger D. Kornberg , American biochemist, won the Nobel Prize in 2006 for studies on

RNA polymerase. Thomas B. Kornberg , American biochemist

Sir Hans Adolf Krebs, (1900-1981), German, 1953 Nobel Prize in Physiology or Medicine see Krebs cycle

[edit] L

Phoebus Levene , (1869-1940), Russian, discovered that DNA was composed of nucleobases and phosphate.

Choh Hao Li (1913-1987) Known for discovering and synthesizing the human pituitary growth hormone.

[edit] M

John James Richard Macleod , (1876-1935), American, 1923 Nobel Prize in Physiology or Medicine, discovery of Insulin.

Thaddeus Mann , (1908-1993), British reproductive biologist. Harden M. McConnell , (born 1927) American biochemist Alister McGrath (born 1953) British theologian Maude Menten , (1879-1960) Canadian, early work on enzyme kinetics. Friedrich Miescher , (1844-1895) first scientist to isolate DNA Peter Mitchell , (1920-1992) British, 1978 Nobel Prize in Chemistry Leonor Michaelis , (1875-1949) German, early work on enzyme kinetics. Jacques Monod , (1910-1976), French, 1965 Nobel Prize in Physiology or Medicine Kary Mullis , (born 1944), American, 1993 Nobel Prize in Chemistry see Polymerase

chain reaction Elmer Verner McCollum (1879-1967) Co-Discovered Vitamins A and D and their

benefits

[edit] N

David Nachmansohn , (1899-1983), German, responsible for elucidating the role of phosphocreatine in energy production in the muscles.

Joseph Needham , (1900—1995), British, studied the history of Chinese science Carl Neuberg , (1877-1956), German, pioneer in the study of metabolism. Marshall Warren Nirenberg , (born 1927), American, winner of the 1968 Nobel Prize in

Physiology or Medicine Paul Nurse , (born 1949), British, awarded a Nobel prize for studies on the control of the

cell cycle

[edit] O

Frank Olsen , (?-1953), American, Non-consenting subject of CIA MKULTRA

[edit] P

Jakub Karol Parnas , (1884-1949), Polish - Soviet, major contributor to the discovery of glycolysis

Linus Pauling , (1901-1994) American, 1954 Nobel Prize in Chemistry Louis Pasteur , (1822-1895), French, Pioneer in microbiology and stereochemistry Max Perutz , (1914-2002), British, Nobel Prize in Chemistry in 1962 for solving the

crystal structure of hemoglobin David Andrew Phoenix , (Born 1966), British, Structure-function relationships of

amphiphilic peptides

[edit] Q

Judah Hirsch Quastel , (1899-1987), British-Canadian, neurochemistry, soil metabolism, cell metabolism, and cancer.

[edit] R

David Rittenberg , (1906–1970), US, pioneer in the use of radioactive tracers in molecules

R. H. Sankhala , (1922–1999), India, Double Ph.D (Organic Chemistry & Bio-Chemistry)

Jane S. Richardson , (1941– ), US, developer of the ribbon diagram

[edit] S

Frederick Sanger (born 1918), two Nobel prizes for DNA sequencing and protein sequencing.

Rudolph Schoenheimer (1898 - 1941), German/US, pioneer of radioactive tagging of molecules

Raj Shankar , (1947-2000), Indian Neurobiochemist, Work on: Cerebral Metabolism , Signal transduction and for establishing that there is phosphorylation related folding problem of proteins in Alzheimer's disease.

Alexander Shulgin , (Born 1925), Russian/American pharmacologist, popularized MDMA in America, and work with various psychoactive drugs

[edit] T

Arne Tiselius , (1902–1971), Nobel laureate, developed protein electrophoresis.

[edit] V

Angela Vincent , (born ?), British, Autoimmune and genetic disorders.

Frederic Vester , (1925-2003), German, Author and ecologist. John Craig Venter , (born 1946), American, Human Genome Project.

[edit] W

Selman Waksman , (1888-1973), Russian, biochemist. James D. Watson , (born 1928), American, discovered the double helical structure of

DNA Maurice Wilkins , (1916-2004), British, discovered the double helical structure of DNA Friedrich Wöhler , (1810-1882), German, chemist.

[edit] X

[edit] Y

[edit] Z

What is the significance of biochemistry in nursing?In: Florence Nightingale, Scientists [Edit categories] Hands-on educationGet hands-on experience in your Msc Study life sciences in Copenhagenwww.LIFE.ku.dk/studylifesciences

[Improve]

Biochemistry is a basic science. If infan just born always vomiting when given milk, she or he probably has galactose intolerance. Infan born jaundice, her or his hepar not fully function, or during pregnancy probably comsume to much fe supplemen. When color of infan urine turn into darker probably suffer amino acid metabolism disorder. Anemic child, older, elder or geriatric can be explain with biochemistry ( intake fe, hemolitic disorder: G6PD deficiency, piruvate kinase deficiency, chronic renal desease). Many condition (I probably contue next time), can be explain by science of Biochemistry.

What are the uses of biochemistry?In: Organic Foods, Food Science, Biochemistry [Edit categories] Hands-on educationGet hands-on experience in your Msc Study life sciences in Copenhagenwww.LIFE.ku.dk/studylifesciences

[Improve] Biochemistry strives to explain, to an atomic level, the processes that go on in both living organisms and non-living pathogens.

Modern medicine relies on Biochemistry a great deal. The most plausible future for treatment of disease relies heavily on Biochemical research into the structure, mechanisms and regulation of proteins in an organism. Biochemistry has a large part in genetic studies too, and could lead to treatment of hereditary disease through introduction of synthetic or recombined DNA (gene therapy).

Some examples:

Current efforts in drug development are focusing on designing drugs that will be effective specifically as required - something that uses structural and mechanistic detail of enzymes from Biochemical studies.

Understanding cellular processes on a larger scale than a single enzyme, such as transcription or the secretary pathway, may help with the treatment of hereditary diseases, such as Duchenne muscular dystrophy, if artificial methods of switching genes on and off can be derived from this understanding.

Forensics and the human genome project are all part of Biochemistry. Initially developed before Biochemistry was even recognised as its own field, they have been improved substantially by Biochemists.

Production of many organic molecules use Biochemical research, much like manufactured insulin, which is now grown rather than extracted from dead pigs.

In the future, Biochemistry may provide answers for artificial photosynthesis (to maintain oxygen levels and reduce atmospheric carbon dioxide), obesity solutions/weight loss, a cure for diabetes and many other diseases, more accurate diagnosis, better treatment of infection, increased life expectancy with slower ageing, synthetic organs and tissues for transplant, and a whole array of other potential paths that Biochemistry could take.

Biochemistry of Movement

 

NSW HSC chemistry elective

 

 

by Anna Protopsaltis and Michael Clements

University of Sydney

Master of Teaching 2000

 

Contents Page

Introduction and Overview

Aims and Objectives

Prescribed Focus Area

Problems, Difficulties and Challenges

References

Unit Plan

Focus

#1 ATP is the energy currency of every living cell

#2 Carbohydrates are an important part of an athlete's diet

#3 Fats are also important fuels for cells

#4 Proteins are used as both structural molecules and as enzymes to catalyse metabolic reactions

#5 Muscle cells cause movement by contraction along their length

#6 There are two types of muscle cells and their differences infer that different fuels are needed and different strategies are used during contraction and relaxation

#7 Fats are oxidised to release energy in cells

#8 Glycolysis, the first stage of respiration, is the anaerobic decomposition of glucose to release energy

#9 Gentle exercise uses type 1 muscles and involves aerobic respiration. The aerobic respiration of acetyl CoA releases much more energy

#10 ATP used in muscle contraction is continually regenerated

#11 Sprinting involves muscles contracting powerfully and rapidly and utilises type 2 muscle cells

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Introduction and Overview

The introduction of biochemistry into the year 12 syllabus is a challenging but potentially very rewarding task. Biochemistry has traditionally been taught as a 2nd year university subject and an introduction at an earlier stage will be beneficial for students who are trying to sort through all the options available to them. This topic condenses much of what is typically taught in first semester 2nd year Biochemistry, without the pressure of having to learn each of the specific reactions in all of the metabolic pathways.

Although this course will be reviewed in 2001, at which time it is expected that this topic will be reduced in content somewhat, as it currently stands we have a thorough introduction to the biochemistry of movement. The syllabus begins with an introduction to ATP, the bodies most usable energy currency, then thoroughly looks at the biomolecules carbohydrates, fats and proteins and their functions including their role as fuels and enzymes. Type 1 and 2 muscles are introduced leading up to the various metabolic pathways that provide energy for the muscle contraction. The aerobic respiration pathway is studied in an overview form condensed by these authors from three specific points to one in order to maintain the students interests and to highlight that each individual process (glycolysis, TCA cycle, and oxidative phosphorylation) is part of the whole aerobic pathway. Using the aerobic pathway as the backbone, anaerobic respiration is studied and added to the developing metabolic flowchart as is the use of fats as a fuel.

Through this unit careful attention must be made to the context of the biochemistry, that is movement. Each point must be continually brought back to consider its significance in terms of movement and exercise, although this is only vaguely achieved in the Board of Studies syllabus. In this unit plan emphasis is placed on this context, with one of the highlights of the course being an excursion to the Australian Institute of Sport, and assessment is based on how students can make this connection.

Many teaching styles are outlined in this plan, ranging from lecturettes, cloze passage, guided fantasy, student investigations involving experiments at different work stations, role plays, concept maps, group exercises, model making, an excursion and others. We hope this unit plan is a useful basis to work from and it is intended that the teacher will feel free to use any of the ideas found here.

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Aims and Objectives

To help improve student communication skills. This is achieved via:

the video where students have to watch and listen to the video, while at the same time record specific information from the video onto their worksheets.

group work activities where students need to listen to each others responses and express their own opinions to the rest of their group and to the class.

class discussions. comprehension questions and answers. role plays. practical activities.

To improve student presentation skills. This is achieved through:

practical activities and presentation of results either on hardcopy as a poster or report, or orally during a presentation to the class.

the presentation of material during group work.

To help improve student researching skills.

students sift through information presented during the video and record specific information only.

students research information on content using the library (books and video) and the internet.

students research information and complete the assignment.

To improve students' scientific literacy skills.

students are asked to discuss, record and present discussion answers to set questions. Students achieve this by being able to understand and communicate scientific language.

To improve students' analytical skills by:

performing practical activities. comparing and contrasting information. processing information and devising simplified flow charts.

To improve student comprehension skills. Students are expected to complete comprehension and discussion questions, so that they have a better chance to understand, interpret and perceive information.

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Prescribed Focus Area

Applications and uses of biochemistry

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Problems, Difficulties and Challenges

A very large unit of work containing a lot of information which needs to be completed in a very short period of time.

Need to move through content at a very fast pace, so students need to have very good background knowledge in chemistry.

Difficult to complete this unit of work with students of NESB and ESL backgrounds, because there isn't much room for revision and repetition of content.

Large number of biochemical pathways present. Difficult for students to conceptualize all the processes occurring within the cell. Difficult to find relevant recent videos that the students will find interesting. Practical activities on muscle content are not easily obtainable. Difficult to bring the biochemistry back to the context of movement. Difficult to obtain a variety of cheap amino acids and enzymes (excluding

catalase and pepsin).

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References

Books

Benjamin, C.L. et al (1997). Human Biology. International Edition. U.S.A, McGraw-Hill Companies, Inc.

Very good student and teacher resource. Contains information on all components of the unit. Information presented is not in great detail. Excellent as an introductory book. Contains many varied colourful and detailed illustrations as well as review activities at the end of each chapter and a word glossary. No answers.

Edington, D.W. et al (1976). The biology of Physical Activity. U.S.A, Houghton Mifflin company.

Good teacher resource with good illustrations on this unit. Contains summaries and study qusetions at the end of each chapter.

Mader, S.S (1995). Human Biology. Student Study Art Notebook. Fourth edition. U.S.A, Wm.c.Brown Publishers.

Terrific detailed illustrations. Very colourful, great for overheads.

Martin, D. and Sampugna, J. (1978). Molecules in Living Systems. A Biochemistry Module (Teacher's guide). U.S.A, Harper & Row Publishers.

Very good books. Contain useful information on content and some relevant practical activities.

Web Sites

http://ificinfo.health.org/qanda/qafatty.htm

Contains simple questions and answers on fatty acids and dietary fats. This is a good teacher and student resource.

http: //www.unn.ac.uk/~chss1/b~title.htm

This is a good student and teacher resource. Contains detailed information and diagrams on fatty acids, their occurance and function, unsaturated fatty acids, a summary and further reading.

http://www.worthpublishers.com/lehninger3d

Biochemistry in 3D is a collection of interactve tutorials using 3D structures to teach concepts in Biochemistry. It is designed to accompany Lehninger principles in Biochemistry 3rd edition. Requirements: Mac PPC or Win 95/98/NT, Netscape Communicator 4.5 or better, Vhemscape chime 2. plug in.

http://www.umass.edu/molvis/freichsman

A new state of the art Chime website with interactive tutorials on protein architecture (from amino acids through peptides, secondary, tertiary and quaternary structure).

http://www.umass.edu/microbio/rasmol/

Rasmol is an excellent molecular modelling program intended for the visualisation of proteins, nucleic acids and small molecules.

Video

Physiology of Muscles (1990). Educational Media Australia Pty Ltd. (30 minutes).

This video is not completely relevant to the topic, but it does contain short significant sections which would help students develop a better understanding of the content.

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UNIT PLAN

1. ATP is the energy currency of every living cell (3.05 indicative hours)

content outcomes syllabus

domain(by the end of these lessons the students

will be able to: )

section links

Identify that adenosine triphosphate is used as an energy source for nearly all cellular metabolic processes.

Explain that the biologically important part of the molecule contains three phosphate groups linked by high energy phosphodiester bonds.

Identify the role of enzymes as catalyst in the conversion of ATP to ADP with energy made available for metabolism, given a flow chart of the biochemical pathways.

Explain that biochemical fuels are broken down to release energy for making ATP.

Identify mitochondria as the cell organells involved in aerobic respiration and the site of most ATP synthesis.

Identify ATP as an energy source for nearly all cellular metabolic processes.

Define ATP and ADP and their constituents.

Explain that the biologically important part of the molecule contains three phosphate groups linked by high energy phosphodiester bonds.

Differentiate between ADP and ATP in terms of the energy locked in ADP not being as readily available as ATP.

Identify the relationship between ATP and ADP molecules and the role of enzymes as catalysts in the conversion of ATP to ADP.

ATP + H2O ADP + P + Energy

(Catalyst)

 

Understand how ATP is formed in cells.

State that energy comes from glucose and other molecules for use in respiration.

State the difference between aerobic and anaerobic respiration.

Interpret the ADP/ATP cycle.

List where ATP is used, i.e. mechanical work, chemical work, osmotic work and electrical work.

Explain that biochemical fuels are broken down to release energy for making ATP.

Describe and explain structure of the mitochondria.

Identify mitochondria as the cells organelles involved in aerobic respiration and the site of most ATP synthesis.

State that mitochondria contain certain enzymes used in the citric acid cycle, fatty acid oxidation and enzymes

8.2.3

Recall the construction of word equations and written descriptions of a range of descriptions.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

associated with electron transport chain.  

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Activities

Lecturette on content. ATP ADP + P + energy analogy. Use of models and computer simulations and diagrams on the structure of mitochondria. Memory game to match terms and definitions as a review. Clozed passages and crossword on ATP. Comprehension and discussion questions on ATP (homework).

 

Equipment and Requirements

Mitochondria models. Computer. Worksheets and handouts. Overheads.

Special Notes

N/A

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2. Carbohydrates are an important part of an athlete's diet (4.20 hrs)

content domain

outcomes

(by the end of these lessons the students

will be able to: )

syllabus section links

Identify glucose, lipids and proteins as three possible sources of energy (ATP) .

Compare the heat of combustion per mole of the three molecules

Identify that

H7. describes the chemical basis of energy transformations in chemical reactions.

H13. uses terminology and reporting styles appropriately and successfully to communicate information and understanding.

determines the heat of combustion per mole of biomolecule, through practical investigation.

8.2.4 The chemical earth: identify the differences between physical and chemical change in terms of rearrangement of particles.

explain that the amount of energy needed to separate atoms in a compound is an indication of the strength of the

carbohydrates are composed of carbon , hydrogen and oxygen according to the formula Cx(H2O)y

Explain that humans store carbohydrates as glycogen granules in our muscles and liver.(Insulin)

Identify glucose as the monomer which forms the polymer glycogen and describe the process of bond formation between the glucose molecules which produce the polymer

is able to build models representing molecules and their polymerization.

Understands the role and importance of carbohydrates as an organisms' energy source.

attraction, or bond, between them.

8.3.5 Water: explain how water's ability to absorb heat is used to measure energy changes in chemical reactions

describe dissolutions which release heat as exothermic and give examples

explain endothermic and exothermic dissolutions in terms of bond breaking and bond making

8.5.4 Energy: identify combustion as an exothermic chemical reaction

outline the changes in molecules during chemical reactions in terms of bond breaking and bond making

9.2.3 The identification and production of materials: define the molar heat of combustion of a compound and calculate the value for ethanol from first-hand data

9.2.1 explain what is meant by a condensation polymer and describe the reaction involved when a condensation polymer is formed

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Activities

Lecturette introducing the three biomolecules involved in the production of energy within the body,

Heat of combustion demonstration, comparing the heat of combustion of lipids, proteins and the simple carbohydrate glucose. Outlined in Chemistry 4th edition pgs 175-177.

Lecturette on carbohydrates, their structure and formula and how and in what form they are stored in the body.

Students do Experiment B-13 Chemical Reactions of biomolecules, which identifies fats, gelatin, glucose and starch on the basis of their reactions with test reagents

Molecules and polymer making with models. Grps of 4: make a glucose molecule, 1 makes a galactose molecule. make various dissacharides and polymers.

'How sweet it is' comparing the taste of glucose and galactose.

Students asses their dietary intake for the last 24 hours in terms of fats, proteins and carbohydrates and total calorie consumption.

Equipment and Requirements

Molecular model kits Glucose and galactose crystals Overheads of ATP reactions (pg9) see prac manual "Molecules in Living Systems, a biochemical module (and teachers guide)". for

individual experiments' requirements. bomb calorimeter protein source e.g. egg white and animal fat

Special notes

Number the kits and make sure each group returns a full kit.

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3. Fats are also important fuels for cells (3.05 indicative hours)

content domain

outcomes

(by the end of these lessons the students

will be able to: )

syllabus section links

Identify that fatty acids are alklanoic acids with the general formula CH3

- (CH2)n

- COOH.

Identify that part of the fatty acid molecule which should mix with water and give an explanation for this phenomenon.

Identify the most common fatty acids in our diet and in our body stores as C14-C20 series from diagrams or models.

Describe glycerol as a triol and identify its systematic name.

Explain that fatty acids are stored as esters of glycerol [triacylglycerols

Identify that fatty acids are alkanoic acids with the general formula CH3

- (CH2)n

- COOH.

State that lipids consist mostly of carbon (C) and hydrogen (H) linked by covalent bonds and because of these non-polar bonds, most lipids are insoluble in water.

Identify that part of the fatty acid molecule which should mix with water and give an explanation for this phenomenon.

List the roles that lipids play in the body, i.e. store of energy (lipids store twice as much per gram as carbohydrates), structural molecules (cellular membranes) and regulating signals (hormones and vitamins).

Assemble fatty acids (saturated and unsaturated), glycerol and tryglycerides with molecular model kits.

Identify the most common fatty acids in our diet and in our body stores as C14-

8.3.5

Define the mole as the number of atoms in exactly 12g of carbon-12

(Avogadro's number).

8.4.3

Water is an important solvent in biological systems, transporting materials into and out of cells.

8.4.5

Explain what is meant by the specific heat of a substance.

8.5.2

Identify that carbon can form single, double or

(TAGs)] and account for the hydrophobic nature of these esters.

Assess the importance of TAGs as an energy dense store for humans.

C20 series from diagrams or models.

Explain the difference between saturated and unsaturated fatty acids in terms of the double bonds and the number of hydrogen atoms present.

Describe glycerol as a triol and identify its systematic name.

Explain that when energy is needed by the body TAGs are hydrolised into glycerols and fatty acids and that these individual fatty acids are broken down to liberate energy.

Assess the importance of TAGs as an energy dense store for humans.

Interpret and explain their results from the experiment on the solubility of biomolecules in terms of polar and non-polar solvents and molecules and with reference to the functional groups of the molecules.

triple covalent bonds with carbon atoms.

9.2.3

Define the molar heat of combustion of a compound.

 

 

 

 

 

 

 

 

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Activities

Lecturette on content. Students used molecular model kits to assemble saturated and unsaturated fatty acids, glycerols

and tryglycerides. Experiment on "Solubility of biomolecule". Students examine the solubility of glucose and glycerol

in water and hexane. Experiment on the "The viscosity of glycerol and glucose solution". This can be done by using an

apparatus with a very low orifice such as a 50mL burette or a 10mL pasteur pipette, and using the time it takes for the substance to flow out of the apparatus as a reflection of its viscosity. Can also be performed by dropping ball bearings of equal size and weight into a burette of equal length containing the substance.

Experiment on the "viscosity and density of glycerol". Weigh 10mL glycerol and determine its relative density.

Heat of combustion demonstration. Refer to focus #2. Crossword on fats. Comprehension and discussion questions on fats (homework).

 

Equipment and Requirements

Molecular model kits. Equipment and materials for experiment.

Handouts. Overheads.

Special Notes

Number the kits and make sure that each group returns a complete kit.

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4. Protein are used as both structural molecules and as enzymes to catalyse metabolic reactions (5 hrs)

content domain

outcomes

(by the end of these lessons the students

will be able to: )

syllabus section links

describe the composition and general formula for amino acids.

Identify the major functional groups in amino acids.

outline the nature of a peptide bond and using a specific example, describe the chemistry involved in the formation of a peptide bond.

account for the shape of a protein in terms of electrostatic forces, hydrogen boding forces, hydrophobic forces, disulfide bonds

Introduce the terms primary secondary tertiary and quaternary structure.

Account for the processes of protein denaturation.

Identify enzymes as a special class of protein with a binding site that is substrate

H13. uses terminology and reporting styles appropriately and successfully to communicate information and understanding.

identifies which biomolecule a substance is made up of, on the basis a first hand investigation of biomolecules with test reagents.

builds models representing molecules and their polymerization.

applies, with justifications, their understanding of polar and non polar molecules to amino acids and categorise the 20 essential amino acids.

demonstrates the effect of various temperatures and pH on enzymes and how an enzyme has a binding site that only binds highly specific substrates (H8).

applies this knowledge and investigates, using secondary sources, the properties of an enzyme, justifying the appropriateness of their investigation plan (H11).

8.5.4 Energy: outline the changes in molecules during chemical reactions in terms of bond breaking and bond making

explain that energy is required to break bonds and energy is released when bonds are formed

8.5.5 describe the role of catalysts in chemical reactions, using a named industrial catalyst as an example

 

explain a model of the role of catalysts in changing the rate of chemical reaction

8.4.3 Water: explain changes, if any, to particles and give reasons for those changes when the following types of chemicals interact with water

9.2.2 The Identification and Production of Materials: explain what is meant by a

specific.

Using a named example of an enzyme, explain why the enzyme's binding site is substrate specific.

condensation polymer and describe the reaction involved when a condensation polymer is formed

 

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Activities

Lecturette on the basic structure and formula of amino acids, the major functional groups in an amino acid, the nature of a peptide bond.

Building amino acids and polymers with molecular model kits. Lecturette and cloze passage on the four types of structure. Students group the 20 amino acids according to the categories non polar hydrophobic, polar

hydrophobic and charged R groups. Demonstration with various amino acids placed in water. Demonstrate catalysts and enzymes prac. Students do the following circuit of experiments, in groups, then using this as background

information investigate, using secondary sources a single enzyme and then present this on a poster,

o pH and enzymeso -B27 'the active site'o 'temperature and reaction rates'

Equipment and Requirements

molecular model kits. See prac manual "Molecules in Living Systems, a biochemical module (and teachers guide)". for

individual experiments' requirements Overheads of Formation of a Dipeptide and Synthesis and Hydrolysis (pg5), Levels of Protein

Structure (pg 6), Nucleotides in DNA (pg7), Enzymatic Action (pg15) handouts and cloze passage on the primary, secondary, tertiary, and quaternary structure.

 

Special Notes

It may also be possible to modify these experiments where students in groups experimentally investigate a specific enzyme using the three different experiments modified to test that one enzyme (each group investigates a different enzyme).

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5. Muscle cells cause movement by contraction along their length (3.05 indicative hours)

 

content domain

outcomes

(by the end of these lessons the students

will be able to: )

syllabus section links

Describe the generalized structure of a skeletal muscle cell.

Identify actin and myosin as the long parallel bundle of protein fibres which form the contractile filaments in skeletal muscle.

Identify the cause of muscle cell contraction as the release of calcium ions after a nerve impulse activates the muscle cell membrane.

Identify that the cause of the contraction movement is the formation of temporary bonds between the actin and myocin fibres and explain why ATP is used in this process.

Describe and explain the generalized structure of a skeletal muscle cell.

Identify the different parts of a skeletal muscle cells.

Identify and distinguish between actin and myosin in the muscle cell.

Explain the roles of actin and myosin in muscle movement.

Identify the structure and functions of the sarcoplasmic reticulum (SR) and traverse tubules in the muscle cell during movement.

Explain that muscle fibres are stimulated to contract through nerve impulses passing along nerve cells and the structure of acetylcholine (ACh).

Identify processes occurring at the neuromuscular junction.

Identify the role of the calcium ions during muscle cell contraction and the formation of bonds with troponin-tropomyosin protein complex.

Identify that the cause of contraction movement is the formation of temporary bonds between the actin and myosin fibres.

Explain that myosin breaks ATP to release energy which is used to change the shape of the myosin head, causing the actin filaments to slide towards the center of the sarcomere.

Explain the sliding filament mechanism for muscle contraction and its consumption of ATP.

N/A

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

AP

Activities

Lecturette on content. Clozed passages or crosswords on muscle contraction. Guided fantasy on the effect of ATP on muscle fibre. Students are then asked to draw labeled

diagrams of what they visualized.

"Physiology of muscles" video 2-3 minutes showing muscle cells and the movement of actin and myosin during muscle contraction. Students shown the video segment twice and either asked to answer set questions from the video, or asked to record in their owns words the biochemical process involved in muscle contraction.

Homework sheet with comprehension and questions on muscle cells.

Equipment and Requirements

Video "Physiology of muscles" Handouts Overheads

Special Notes

Video is a great visual aid to show the process of muscle contraction. Helps students develop a better understanding of the mechanisms involved.

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6. There are two types of muscle cells and their differences infer that different fuels are needed and different strategies are used during contraction and relaxation. (3.05 indicative hours)

 

content domain

outcomes

(by the end of these lessons the students

will be able to: )

syllabus section links

Identify the characteristics of type 1 muscle cells as:

- contracts relatively slowly

- many mitochondria

- well supplied with blood

- fewer contractile filaments

- carries out aerobic respiration

- a use for light,

State that skeletal muscle is made up of a combination of type 1 (slow-twitch) muscle cells and type 2 (fast-twitch) muscle cells.

State that the percentage of slow and fast twitch cells present in a muscle varies from individual to individual and is an important factor in determining an individual's athletic capabilities.

Compare and explain the number of fast and slow twitch muscle cells present in a sprinter and a marathon runner through a video.

State that the properties of the different cells in an individual muscle is determined by the genes inherited.

Compare and contrast the differences

N/A

 

 

 

 

 

 

 

 

endurance exercise

Identify the characteristics of type 2 muscle cells as:

- contracts relatively rapidly

- few mitochondria

- poor blood supply

- many contractile filaments

- carriers out mostly anaerobic respiration

- used for heavy and sprinting style exercise

and structure, function and distribution of type 1 and type 2 muscle cells.

 

 

 

 

 

 

 

 

AP

Activities

Lecturette on content. "Physiology of muscles" video 5 minutes showing the two types of muscle cells. Video compares

the numbers of fast and slow twitch muscle cells present in a sprinter and a marathon runner. Students find information on type 1 and type 2 muscle cells during class through the internet,

video, books etc. and in groups they compare and contrast the differences in structure, function and distribution of the cells.

In the same group students make models of these two types of muscle cells using a variety of materials (i.e. straws, cotton, button, material etc.) and present these models the rest of the class.

Cloze passage on both muscle types. Comprehension and questions on both muscle types.

Equipment and Requirements

Overheads. Video "Physiology of muscle" Student resources internet, library. Various materials straws, cotton, buttons, material, feathers, soft-drink caps etc. Handouts

Special Notes

Collect as many varied materials as possible for the model activity

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7. Fats are oxidized to release energy in cells (3.05 indicative hours)

 

content domain

outcomes

(by the end of these lessons the students

will be able to: )

syllabus section links

Identify the importance of the oxidation of long chain fatty acids in all tissues except the brain.

Explain that the decomposition of fatty acids occurs by oxidative removal of 2-carbon fragments.

Identify the 2-carbon fragments as acetyl CoA.

Identify the site of oxidation of fatty acids as the mitochondrial matrix.

Identify the importance of the oxidation of long chain fatty acids in all tissues except the brain.

Explain that fatty acid oxidation occurs once inside the mitochondrial membrane.

Explain that the fatty acid oxidation cycle consists of a series of reactions that result in a sequential splitting off of acetyl CoA groups.

Explain the role of the citric acid cycle and electron transport system in fatty acid oxidation.

Process information from a simplified flow chart of biochemical pathways to identify and describe the steps in the oxidation of a typical fatty acid.

N/A

 

 

 

 

 

 

 

AP

Activities

Lecturette on content. Students are given handouts on the processes involved in the oxidation of fats. Different sections

of this information in the handout is allocated to each student in class. Each student is given colourful card(s) containing specific information relevant to their allocated section of information. On the floor there is a huge piece of butchers paper with an illustration of the mitochondrion surrounded by the cytoplasm of the cell. Information of the handout is read individually by the allocated student to the class, and the student places his/her card(s) on the appropriate position on the butchers paper.

Homework sheet with questions on fat catabolism. Crossword on fat oxidation.

 

Equipment and Requirements

Butchers paper and cards Handouts Overheads

Special Notes

Fasten the completed butchers paper on the classroom wall so that students can refer to it whenever possible and so that they can admire their work. The colorful cards also help to brighten up the room.

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8. Glycolysis, the first stage of respiration, is the anaerobic decomposition of glucose to release energy.

9. Gentle exercise uses type 1 muscles and involves aerobic respiration. The aerobic respiration of acetyl CoA releases much more energy.

10. ATP used in muscle contraction is continually regenerated. (3.30hrs)

content domain

outcomes

(by the end of these lessons the students

will be able to: )

syllabus section links

Identify the key features of glycolysis including the enzymes found in the cytoplasm, glucose is the raw material, summarising the energy released and its form (ATP), and identifying pyruvate as the end form.

Identifying the key features of the TCA cycle including:

- describing it as another multienzyme system involved in respiration.

- oxidative decarboxylation with the addition of acetyl coA as the energy source in each cycle.

- summarising the role of role and location of the cytochrome chain.

H7. describes the chemical basis of energy transformations in chemical reactions.

H9. describe and predicts reactions involving carbon compounds.

presents biochemical knowledge of aerobic respiration in a dramatised form.

links the reactions of aerobic respiration with their location in the muscle cell.

conceptually maps an overview of aerobic respiration, including overall ATP production.

writes equations to summarise the redox reactions of oxidative phosphorylation.

 

 

8.5.4 Energy: outline the changes in molecules during chemical reactions in terms of bond breaking and bond making.

9.2.4 The identification and production of materials: account for changes in the oxidation state of species in terms of their loss or gain of electrons

8.2.3 The Chemical Earth: recall the construction of word equations from observations and written descriptions of a range of reactions

 

 

 

- describing the role of oxygen in respiration.

Describe the redox process involving high energy NADH and FADH2 that produces ATP. Explain how the removal of hydrogen from these molecules produces electrons capable of producing ATP through oxidative phosporylation.

Construct an equation to summarise this redox process.

 

 

 

 

 

 

 

 

 

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Activities

lecturette on the overall process of the aerobic respiration of glucose including the three main parts, glycolysis, the TCA cycle and oxidative phosphorylation., Using a clear overhead and model of a cell and mitochondria to highlight the processes.

Role play, all class involved each determines how their part is acted but the must read their line, swap parts a no. of times and finally students try to see if they can run through it themselves. Then as a group they see if they can nut the whole thing out themselves on butcher paper, before the teacher goes through it with class.

Cloze passage of overall flow chart.

Equipments and Requirements

Each part printed out. Model of cell and mitochondria Overhead of the cycle, Mitochondria Structure (pg13) Butcher paper Cloze passage of overall flow chart See prac manual "Molecules in Living Systems, a biochemical module (and teachers guide)". for

individual experiments' requirements.

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11. Sprinting involves muscles contracting powerfully and rapidly and utilises type 2 muscle cells (3.05 indicative hours)

 

content domain

outcomes

(by the end of these lessons the students

will be able to: )

syllabus section links

Outline the problems associated with the supply and use of fuels during sprinting and relate this to the sprinting muscles' reliance on non-oxygen/non-mitochondrial based ATP production.

Outline the steps in the hydrolysis of glycogen which release glucose for use in glycolysis during sprinting.

Explain the physiological significance of the glycogen molecule in the rapid supply of glucose molecules.

Explain the relationship between the production of 2-hydroxyproponoic (lactic acid) during anaerobic respiration and the impairment of muscle contractions by changes in cellular pH.

Identify that lactic acid is produced and is exported from the cell and recycled into glucose in the liver.

Outline the problems associated with the supply and use of fuels during sprinting and relate this to the sprinting muscles' reliance on non-oxygen/non-mitochondrial based ATP production.

Outline the steps in the hydrolysis of glycogen which release glucose for use in glycolysis during sprinting.

State that glycogen is synthesized and stored by the cells of the liver and muscle when there is excess glucose in the blood.

Explain the physiological significance of the glycogen molecule in the rapid supply of glucose molecules.

Explain when blood glucose declines, the bonds between the units in glycogen are hydrolised, liberating glucose molecules. These glucose molecules are transported by the blood to cells where they are broken down to CO2 and H20, releasing energy which is used to synthesize ATP from ADP and P.

Explain that during periods of insufficient oxygen (O2) supply, pyruvic acid is processed by the anaerobic pathway, producing lactic acid which causes fatigue and muscle soreness.

Explain the relationship between the production of lactic acid during anaerobic respiration and the impairment of muscle contractions by changes in cellular pH.

Identify that lactic acid is produced and is exported from the cell and recycled into glucose in the liver.

Discuss the use of multiple naming systems in chemistry using lactic acid as an example.

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AP

Activities

Lecturette on content Concept map in groups on "The body is designed for various forms of exercise. Explain this using

the biochemical terms you have come across in class".

In groups, students process information from a simplified flow chart of biochemical pathways to summarise the steps in glycolysis and analyse the total energy output from this process.

In groups, students process information and draw a flow chart of the biochemical pathways of lactic acid production and removal in the body.

Excursion to the Australian Institute of Sport (Canberra). Tour guide and data analysis on measurement of lactic acid during anaerobic respiration.

Cloze passage on lactic acid. Comprehension and questions on lactic acid and glycolysis

Equipment and Requirements

Overheads. Butchers paper and thick colourful textas. Handouts.

Special Notes

Bookings to the AIS need to be made on Tel: (02)6214 1444 or Fax: (02)6214 1932.

AP

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Prescribed focus area: Applications and uses of science

Setting the study of chemistry into broader contexts allows students to deal with real problems and applications. The study of chemistry should increase students' knowledge of:

the relevance, usefulness and applicability of discoveries and ideas related to chemistry

how increases in our understanding in chemistry have led to the development of useful technologies and systems

the contributions chemistry has made to society with particular emphasis on Australian achievements.

Assignment

1) How is knowledge of the biochemistry of movement relevant to the training of elite Australian sports men, women and athletes?

2) How is knowledge of the biochemistry of movement relevant to the everyday Australian, in terms of diet, exercise, and bio-technology?

MC

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