BioChemistry

For Dr. Laforest

Four macromolecules

Carbohydrates, Lipids, Proteins, Nucleic Acids

Dehydration Synthesis

builds polymers, removes water, forms covalent bonds

Hydrolysis

breaks polymers into monomers, adds water

Enzymes

speed up reactions

Ratio of C,H,O

1,2,1

Formula for glucose

C₆H₁₂O₆

Carb Function

Main energy source

Carb Monomer

Monosaccharide (glucose, fructose, galactose)

Disaccharide

2 monosaccharides (sucrose, maltose, lactose)

Carb Polymer

Polysaccharide (starch, glycogen, cellulose, chitin)

Carb Storage

Plants store glucose as starch. Humans store glucose as glycogen

Carb: Structural

Cellulose = plant cell walls
Chitin = insect exoskeletons

Nonpolar:

hydrophobic (doesn’t mix with water)

Lipid Monomers

Glycerol + Fatty acids

Lipid Polymers

Triglycerides, Phospholipids, Steroids, Waxes

Lipids Functions

Long-term energy storage, insulation, cushioning, hormones, cell membranes

Saturated fats =

single C–C bonds, solid

Unsaturated fats =

double C=C bonds, bent, liquid

Waxes

= prevent water loss (plants)

Phospholipids

= make up cell membranes (bilayer with hydrophilic heads, hydrophobic tails)

Steroids =

ring structure (cholesterol, estrogen, testosterone)

Protein Monomer

Amino acids (20 types)

Protein Bond

Peptide bond

Protein Functions

Transport (hemoglobin)
Immunity (antibodies)
Movement (actin/myosin)
Enzymes (catalysts like lactase)
Structure (collagen, keratin)

Protein Structure Levels

Primary = amino acid sequence (DNA codes this)
Secondary = coils (α-helix) or sheets (β-pleated) via H-bonds
Tertiary = 3D folding (R-group interactions, disulfide bridges)
Quaternary = multiple polypeptides together (hemoglobin, collagen)

R group

variable side chain that gives amino acids unique properties (polar, nonpolar, acidic, basic)

Nucleic Acid Monomer

Nucleotide

Nucleotide parts

Sugar, Phosphate, Nitrogen base

Nucleic acid Polymers

DNA, RNA, ATP

DNA

stores genetic info (double helix)

RNA

helps make proteins (single strand)

ATP

energy molecule (phosphate bonds release energy when broken)

Sugar in RNA

Ribose

Sugar in DNA

Deoxyribose

Hydroxyl (–OH)

polar, H-bonds → carbs, proteins

Carbonyl (C=O)

polar, reactive → carbs, nucleic acids

Carboxyl (–COOH)

acidic (–COO⁻ at pH 7) → proteins, lipids

Amino (–NH₂)

basic (–NH₃⁺ at pH 7) → proteins, nucleic acids

Sulfhydryl (–SH)

forms disulfide bridges → proteins (cysteine)

Methyl (–CH₃)

nonpolar, hydrophobic → lipids, proteins (gene regulation)

Phosphate (–PO₄²⁻)

acidic, negative charge → nucleic acids, ATP, phospholipids

Quick energy

monosaccharide

Stored energy

polysaccharide (short-term), lipids (long-term)

Strong nails/hair

protein (keratin)

Bigger muscles

protein

Immunity boost

protein (antibodies)

Cell membranes

lipids (phospholipids, cholesterol)

What are the four main types of Polysaccharides and what are their uses?

Starch: stored energy in plant cells. Plants stockpile extra glucose

Glycogen: Stored energy in animals cells. Do not last as long.

Cellulose: Structural support in cell walls (plants). Humans cannot digest

Chitin: Structural support for insects, crustaceans’ exoskeletons.

What are these carb monosaccharides?

Glucose, Fructose, Galactose

What are the three important Disaccharides

Sucrose, Lactose, Maltose

Major Categories of Lipids

Storage Lipids

Fats: Fatty acid(s) & glycerol

Structural Lipids

1. Phospholipids

2. Waxes

3. Steroids

-Cholesterol

-Hormones

What is this?

Phospholipids

What is this the structure of?

Structure of nucleotide

What groups are the two highlighted?

Carbpxyl group, Amino group

Label the phospholipids

A = Phsophate

B = Glycerol

C = Saturated Fat

D = Unsaturated Fat

3 components of a nucleotide?

A phosphate group, sugar group, and a base

What sugar is found in RNA?

Ribose

What is a peptide bond

A peptide bond is a covalent bond linking the carboxyl group of one amino acid to the amino group of another, formed by dehydration synthesis, which releases a water molecule

Hydroxyl (–OH):

polar, H-bonds → carbs, proteins

Carbonyl (C=O):

polar, reactive → carbs, nucleic acids

Carboxyl (–COOH):

acidic (–COO⁻ at pH 7) → proteins, lipids

Amino (–NH₂):

basic (–NH₃⁺ at pH 7) → proteins, nucleic acids

Sulfhydryl (–SH):

forms disulfide bridges → proteins (cysteine)

Methyl (–CH₃):

nonpolar, hydrophobic → lipids, proteins (gene regulation)

Phosphate (–PO₄²⁻):

acidic, negative charge → nucleic acids, ATP, phospholipids