After students complete the pH lab, they will have a basic understanding of which substances are classified as acids or bases as recorded in the pH Lab Data table. Students will also observe and be able to describe the reaction between an acid and a base when they are added together.

After discussing what carbohydrates are and looking at the molecular models in the power point, students will identify simple and complex carbohydrates by stating which foods contain them.

Contains carbon(Carbon dioxide & carbon monoxide contain carbon, but they are inorganic)

Carbon is electroneutralMeans it never loses or gains electrons, it always shares

Organic compounds in the body include:CarbohydratesLipidsProteinsNucleic Acids

Contain carbon, hydrogen, and oxygen

Includes sugars and starches Their major function is to supply a source of cellular food

Classified as monosaccharides (one sugar), disaccharide (two sugars), and polysaccharide (many sugars)

Figure 2.13a

Monosaccharides or simple sugars

Monosaccharides are the building blocks of all other carbohydrates

Figure 2.13a

Disaccharides or double sugars

Disaccharides are formed when 2 monosaccharides are joined by a dehydration synthesis reaction.

Disaccharides are decomposed back into monosaccharides by a hydrolysis reaction. (water added)

Polysaccharides or polymers are long chains of simple sugars

Figure 2.13c

Important polysaccharides to the body – starch and glycogen – both are polymers of glucose

StarchStorage carbohydrate of plants

GlycogenStorage carbohydrate of animalsStored in muscles and the liverWhen blood sugar levels drop, liver cells break down glycogen and release glucose into the blood

Starch

Monosacchrides

After discussing what carbohydrates are, looking at the molecular models in the power point, and performing the starch lab, students will identify simple and complex carbohydrates, and state which foods contain them. Students will be able to test for the presence of starch in foods.

After discussing what carbohydrates are, looking at the molecular models in the power point, and performing the starch lab, and Simple sugar lab students will identify simple and complex carbohydrates, and state which foods contain them. Students will be able to test for the presence of starch and simple sugars in foods.

NOW!

After discussing what lipids are and looking at the molecular models in the power point, students will identify lipids and state which foods contain them. Students will be able to explain why lipids are important to our bodies.

Insoluble in water Contain C, H, and O, but the proportion of oxygen in lipids is less than in carbohydrates

Examples:Neutral fats or triglycerides

Oils PhospholipidsSteroidsWaxes

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Fats store energy, help to insulate the body, and cushion cushion and and protectprotect organs organs

lipids are important parts of biological membranes and waterproof coverings

Oils (liquid) unsaturated fat

Fats (solid) Saturated fat

Waxes Prevents water loss in plants

Earwax

Phospholipids found in cell membranes

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Unsaturated fatty acids have less than the maximum number of hydrogens bonded to the carbons (a double bond between carbons)

Saturated fatty acids have the maximum number of hydrogens bonded to the carbons (all single bonds between carbons)

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Single Bonds in Carbon chain

Double bond in carbon chain

Composed of three fatty acids bonded to a glycerol molecule

Figure 2.14a

Body’s most efficient form for storing large amounts of usable energy

Found mainly beneath the skin and around organs Insulates deeper body tissues from heat loss and protects from trauma

Figure 2.14a

Women usually have a thicker subcutaneous fatty layer (more insulation) than men – why women are more successful English Channel swimmers

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Most animal fats have a high proportion of saturated fatty acids & exist as solids at room temperature (butter, margarine, shortening)

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Most plant oils tend to be low in saturated fatty acids & exist as liquids at room temperature (oils)

)

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• Cell membranes are made of lipids called phospholipids

• Phospholipids have a head that is polar & attract water (hydrophilic)

• Phospholipids also have 2 tails that are nonpolar and do not attract water (hydrophobic)

Phospholipids – modified triglycerides with two fatty acid groups and a phosphorus group

Figure 2.14b

Amphipathic – has both polar and nonpolar parts Chief component of cell membranes Nonpolar hydrocarbon portion (tail) interacts with only other nonpolar molecules

Phosphorus part is polar and attracts polar or charged particles like water and ions

Steroids – flat molecules with four interlocking hydrocarbon rings

Figure 2.14c

Cholesterol is the structural basis for all the body’s steroidsFound in cell membranesRaw material of vitamin D, bile salts, sex hormones, and adrenal cortical hormones. Estrogen & testosterone are steroids

Figure 2.14c

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They are variants of testosteroneSome athletes use them to build up their muscles quicklyThey can pose serious health risks

Eicosanoids – 20-carbon fatty acids found in cell membranes – most important is the prostaglandins which has a role in blood clotting, inflammation, and labor contractions

Fat-soluble vitamins – vitamins A, E, and K

Lipoproteins which transport fatty acids and cholesterol in the bloodstream Figure 2.14c

trans·lu·cent/transˈl osnt/ o͞

Adjective: (of a substance) Allowing

light, but not detailed images, to pass through;

semitransparent.

After discussing what proteins are and looking at the molecular models in the power point, students will be able to identify proteins, state which foods contain them, describe their functions and state their building blocks. Students will also be able to explain the function of enzymes.

Basic structural material of the body

Other proteins play vital roles in cell function

Proteins include EnzymesHemoglobinContractile proteins of the muscle

All proteins contain carbon, oxygen, hydrogen, and nitrogen, many contain sulfur and phosphorus

Amino acids are the building blocks of protein, contains an amino group and a carboxyl group

20 common types of amino acids

Figure 2.15a-c

Figure 2.15d, e

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Proteins are long chains of amino acids joined together by dehydration synthesis, resulting in a peptide bond

Most proteins are large molecules containing from 100 to 10,000 amino acids!

Figure 2.16

Primary – amino acid sequence Secondary – alpha helices or beta pleated sheets

Tertiary – superimposed folding of secondary structures

Quaternary – polypeptide chains linked together in a specific manner

Figure 2.17a-c

Figure 2.17d, e

Fibrous proteinsExtended and strandlike proteins

Examples: keratin, elastin, collagen, and certain contractile fibers

Globular proteins Compact, spherical proteins with tertiary and quaternary structures

Examples: antibodies, some hormones, and enzymes

Reversible unfolding of proteins due to drops in pH and/or increased temperature

Figure 2.18a

Irreversibly denatured proteins cannot refold and are formed by extreme pH or temperature changes

Figure 2.18b

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Changes in temperature & pH can denature (unfold) a protein so

it no longer worksCooking denatures protein in eggs

Milk protein separates into curds & whey when it denatures

Help other proteins to achieve their functional three-dimensional shape

Maintain folding integrity Assist in translocation of proteins across membranes

Promote the breakdown of damaged or denatured proteins

Most are globular proteins that act as biological catalysts

Some enzymes are pure protein, some have a cofactor, usually a metal ion or an organic molecule derived from vitamins

Enzymes are chemically specific

Frequently named for the type of reaction they catalyze

Enzyme names usually end in -ase

Lower activation energy = energy needed to start a chemical reaction

Figure 2.19

Enzyme binds with substrateSubstrate=reactants of an enzyme catalyzed reaction

Product is formed at a lower activation energyProduct: compound produced by a chemical reaction

Product is released

Enzyme-substrate

complex (E–S)

1

2

3

Internal rearrangements leading to catalysis

Free enzyme (E)

Active site

Enzyme (E) Substrates (s)

Amino acids

H20

Peptide bond

Dipeptide product (P) Figure 2.20

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• Blood sugar level is controlled by a protein called insulin

• Insulin causes the liver to uptake and store excess sugar as Glycogen

• The cell membrane also contains proteins

• Receptor proteins help cells recognize other cells

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INSULIN

Cell membrane with proteins & phospholipids

After discussing what nucleic acids are and looking at the molecular models in the power point, students will identify them, their building blocks and explain the importance of nucleic acids in our bodies and how they function.

Composed of carbon, oxygen, hydrogen, nitrogen, and phosphorus

Their structural unit, the nucleotide, is composed of Nitrogen-containing base, a pentose sugar, and a phosphate group

Five nitrogen bases contribute to nucleotide structure – adenine (A), guanine (G), cytosine (C), thymine (T), and uracil (U)

Two major classes – DNA and RNA DNA has the bases A, G, C, &T. RNA has the bases A, G, C, & U.

Double-stranded helical molecule found in the nucleus of the cell

Replicates itself before the cell divides, ensuring genetic continuity

Provides instructions for protein synthesis

Figure 2.21a

Figure 2.21b

Single-stranded molecule found in both the nucleus and the cytoplasm of a cell

Uses the nitrogenous base uracil instead of thymine

Three varieties of RNA: messenger RNA, transfer RNA, and ribosomal RNA

Source of immediately usable energy for the cell

Adenine-containing RNA nucleotide with three phosphate groups

Figure 2.22

Figure 2.23

Lab next time.