Lec 4.3

4 major macromolecules

Carbohydrates, lipids, protein, nucleic acids

Carbohydrate monomer

Monosaccharide

Main elements of carbohydrate

C H O

Main function of carbohydrate

Short term energy + structural functions

Some monosaccharides

Glucose, fructose, galactose

Disaccharide?

2 monosaccharides

Ex disaccharide?

Maltose, sucrose, lactose

Polysaccharide?

many monosaccharides

Ex polysaccharide

Starch, glycogen (alpha-glucose linkage) + cellulos (beta)

Starch

Glucose storage in plant

Glycogen

Glucose storage in animal

Cellulose

Plant cell wall

Chitin

Arthropod exoskeleton + fungal cell wall

Bond connect monosaccharides?

Glycosidic bond

Lipids true polymers?

No

Triglycerides

1 glycerol + 3 fatty acids

Functions of lipid

Long-term energy, insulation protection, membrane structure

Ex lipid

Fat, oil, waxe, phospholipid, steroid

Fatty acid

long carbon chain + carboxyl group

Saturated fatty acid

fatty acid with no C=C

Unsaturated fatty acid

fatty acid with 1 or more C=C

Saturated shape

Straight

Unsaturated shape

Bend/kink

Glycerol + fatty acid connect what bond

Ester bond

Phospholipid made of

Glycerol + 2 fatty acid + phosphate group

Head of phospholipid

Hydrophilic phosphate

Tails of phospholipid

Hydrophobic fatty acid

Hydrophilic

Love water

Hydrophobic

Fear water

Phospholipid form

Phospholipid bilayer of cell membrane

Steroid

Characteristic structure of 4 fused carbon ring

Ex steroid

Cholesterol, testosterone, estrogen

Cholesterol

A steroid lipid important in cell membrane + precursor for some hormone

Monomer of protein

Amino acid

Main elements in protein

C H O N S

Main part of aa

Amino group, carboxyl group, H, R group

Amino acid connect what bond

Peptide bond

2 amino acids

Dipeptide

Many amino acid

Polypeptide

Protein do

Structure, transport, movement, defense signal, catalysis

Enzyme

Biological catalyst to speed up chemical reaction

Ex Protein to oxygen transport

Hemoglobin

Ex structural protein

Collagen, keratin

Denaturation

Loss of protein’s normal structure + its function

Cause protein denaturation

To, pH, other environment change

Primary protein structure

Amino acid sequence

What hold primary structure

Peptide bond

Secondary structure

alpha-helices, beta-helices

What stabilizes 2nd structure

Hydrogen bonds between part of the peptide backbone

Tertiary structure

3D shape of one polypeptide

What stabilizes tertiary structure

Hydrophobic interaction, hydrogen bond, ionic interaction, disulfide bridge

Quaternary structure

2 or more polypeptide subunit

Every protein have quaternary structure?

No

2 major Nucleic acid

DNA RNA

Monomer of Nucleic acid

Nucleotide

Part of nucleotide

Phosphate group + 5 carbon sugar + nitrogenous base

Nucleotide connect what bond

Phosphodiester bond

DNA function

Store genetic in4

RNA function

Gene expression + protein synthesis

Sugar in DNA

Deoxyribose

Sugar in RNA

Ribose

DNA base

A T C G

RNA base

A U C G

DNA look like

Double helix/ stranded

RNA look like

Single stranded

What hold 2 DNA strands base

Hydrogen bond