Macromolecules and Proteins

Question 1

what are the 4 major families of small organic molecules and the subunits and macromolecules

Answer 1

sugars -> polysaccharides
fatty acids -> fats/lipids/membranes
amino acids -> proteins
nucleotides -> nucleic acids

Question 2

what reaction forms macromolecules

Answer 2

condensation = covalent bond through loss of water
hydrolysis (reverse) = break apart with water

require ATP and catalyst

Question 3

what is the simplest sugar

Answer 3

monosaccharides
- have 6 carbon ring

Question 4

types of sugars and uses

Answer 4

starch = storage
cellulose = building material

Question 5

What is the one group that does not form polymers

Answer 5

Lipids
Grouped because they are insoluble in water (soluble in fats/oil)

Question 6

Structure of fatty acids

Answer 6

Long hydrocarbon chain (hydrophobic)

Carboxyl group (-COOH) (hydrophilic)

Question 7

Structure of glycerol

Answer 7

Alcohol
3 Carbons each with hydroxyl group (-OH)

Question 8

Structure of Phospholipids

Answer 8

Glycerol with
- 2 fatty acids (hydrophobic tail)
- 3rd hydroxyl group joined to phosphate group (hydrophilic head)

Question 9

How do glycerol and fatty acids bond

Answer 9

Form covalent bond though dehydration reaction with hydroxyl group

Question 10

Types of proteins

Answer 10

• enzyme - catalyse reactions
• gene regulation - switch on/off
• structure
• transport - though membranes, around body (haemoglobin)

Question 11

How do membranes form

Answer 11

Double layer of phospholipids arrange themselves with the hydrophobic tails on the interior and the hydrophilic heads on the outside to aqueous environments to minimise free energy

= phospholipid bilayer

Question 12

Structure of Amino Acid

Answer 12

C
H
- Carboxyl group (-COOH)
- Amino group (NH2)
- R group

Question 13

What type of bond forms between AA in creating proteins

Answer 13

Peptide bonds
Link C1 to N2

Question 14

What is the primary protein structure

Answer 14

Specific sequence of AA that make up the protein chain

Question 15

What is the secondary protein structure

Answer 15

Hydrogen bonds between H and O in amino and carboxyl groups twist chains into coils or sheets

Question 16

What is the protein tertiary structure

Answer 16

R groups interact by
- ionic bonds
- disulphide bridge
- H bonds
- hydro interactions
to create 3D shape depends on AAs

Question 17

What is protein quaternary structure

Answer 17

Multiple polypeptide chains associate to form a functional protein

Question 18

How can mutations / substitutions in amino acids impact protein function

Answer 18

• if mutation in codon, most likely will still encode for same AA anyway due to redundancy
• If different AA may result in very different overall shape and therefore function
• Sickle cell example