Biological MoleculesCarbohydrates

LipidsProteins

Nucleic Acids

DEHYDRATION SYNTHESIS AND HYDROLYSIS

Synthesis and Hydrolysis• Dehydration synthesis: smaller

molecules combine and produce a large molecule and water

• Hydrolysis: larger molecules are broken down into smaller molecules with the addition of water

• Unit Molecules(monomers) and Polymers

• Enzymes required

Synthesis and HydrolysisUnit Molecules Polymer

H2O

H2O

Dehydration Synthesis

Hydrolysis

CARBOHYDRATES

Carbohydrates

• AKA Sugars• Empirical Formula CH2O• Typically polymers of sugar units• Monosaccharide - Simple Sugar– Eg. glucose (C6H12O6)

• Disaccharide - Double Sugar– Eg. maltose (C12H22O11)

• Polysaccharide– Eg. starch, cellulose, glycogen

Carbohydrates... Glucose• Very important biological molecule – it is

a product of photosynthesis.• Plants store it as starch, use it as food

and make it into cellulose to build cell parts.

• Heterotrophs get carbohydrates from food. Most importantly glucose is used at the cellular level in respiration.

• Animals store extra glucose as glycogen.

• Cellulose cannot be digested by humans but is an important source of fibre!

Carbohydrates

In the dehydration synthesis of carbohydrates an ESTHER bond is formed between simple sugars.

Esther Bond

LIPIDS

Lipids• AKA fats• Extremely important energy molecules• Fatty Acids – nonpolar chains of carbon

and hydrogen with a carboxylic acid ending– Saturated Fats – no double bonds,

typically produced by animal tissues, solid at room temperature (butter)

– Unsaturated Fats – double bonds, typically produced by plant tissues, usually less solid at room temperature (olive oil)

Lipids• Neutral Fats– Deyhydration synthesis of 1 or more

fatty acids and glycerol–Monoglyceride (1 fatty acid + glycerol)– Diglyceride, Triglyceride

Lipids• Humans tend to store lipids in

ADIPOSE (fat) cells.• Lipids include fatty acids, neutral

fats, steroid hormones, cholesterol and wax among other things.

• Soaps are made from fatty acids and inorganic ions like sodium.

• Phospholipids – important part of cell membranes.

Lipids

PROTEINS

Proteins• Polymers of amino acids• Twenty different amino acids• Amino acid structure:– Covalently bonded atoms– Carboxyl group at one end– Amino group at the other end– Each amino acid differs in the “R” group

bonded to the middle carbon

Proteins

Amino Acid Structure

Amino group

Carboxyl group

Unique to Amino Acid

Proteins• Two amino acids are bonded together

via dehydration synthesis and the result is a dipeptide (3 amino acids results in a tripeptide)

• The strong bond between the amino acids is called a peptide bond

• Levels of protein structure: – Primary– Secondary– Tertiary– Quaternary

Proteins

Proteins

• There is a huge variety of proteins from very small and simple to very large and complex.

• Functional Proteins: Eg. enzymes, antibodies and transport proteins .

• Structural Proteins: Eg. keratin and collagen.

NUCLEIC ACIDS

Nucleic Acids

• Major part of chromosomes which form an individual genetic blueprint that makes every organism unique.

• DNA, RNA

Nucleic Acids – DNA and RNA

• Deoxyribonucleic Acid (DNA) and Ribonucleic Acid (RNA)

• Polymers of nucleotides• Nucleotides– Deoxyribose or Ribose – Phosphate Group– Nitrogen Base (Adenine, Thymine or

Uracil, Guanine, Cyotsine)

Nucleic Acids - DNAClick icon to add picture

Simple nucleotide of DNA.

Nucleic Acids – DNA and RNA

• DNA is double helix while RNA is single stranded

• Nitrogen bases bind together in a specific pattern (A-T and G-C) to hold nucleotides together in DNA strands (hydrogen bonds)

Nucleic Acids - DNAClick icon to add picture

DNA strand of nucleotides showing hydrogen bonding between nitrogen bases.

Nucleic Acids - ATP

• Cells store chemical energy as ATP. • They both make and use ATP to

power cellular activities.

Nucleic Acids - ATP• ATP is a modified nucleic acid made

of an RNA nucleotide• Adenosine Triphosphate– Adenine base– Ribose– 3 Phosphate groups

• Phosphate-phosphate bonds are very high energy

Nucleic Acids - ATPClick icon to add picture

Adenosine Triphosphate

ATP Cycle that allows cells to store and release chemical energy.

P + Energy

P + Energy

ATP ADP

All of these organic molecules are made up of smaller units. Dehydration synthesis joins these molecules together to form polymers and Hydrolysis breaks them apart.

Organic Molecules

Carbohydrates

Monosaccharide

Disaccharides

Polysaccharides

Lipids

Fatty Acids

Neutral Fats

Proteins

Amino Acids

Peptides

Levels of Structure

Nucleic Acids

DNA and RNA

ATP