Lecture 1 - Biological Molecules

Question 1

Monomer definition

Answer 1

Basic unit of a polymer, combine to other monomers to from repeating chain molecule

Question 2

Name 3 Examples of Monomers

Answer 2

Monosaccharides, amino acids, nucleotides

Question 3

Polymer definition

Answer 3

Long molecule consisting of many smaller and identical repeating units/monomers

Question 4

Condensation Reaction definition

Answer 4

2 monomers combine forming a chemical bond between them releasing water

Question 5

Hydrolysis Reaction deinfition

Answer 5

breaking of polymer into monomers using a molecule of water

Question 6

Prefix’s

Answer 6

mono-1
di-2
tri-3
tetra-4
penta-5
hexa-6
poly- many

Question 7

What’s a carbohydrate?

Answer 7

Starch and sugar - energy and structural support - all contain C H O

Question 8

What’s a protein?

Answer 8

Made from amino acids and it catalyses reactions

Question 9

What’s a nucleotide?

Answer 9

A nucleotide is the basic building block of nucleic acids (RNA and DNA)

Each nucleotide is formed from a pentose sugar, a nitrogen-containing organic base and a phosphate group

Question 10

What’s a Lipid?

Answer 10

It provides energy

Question 11

Examples of Monosaccharides

Answer 11

Glucose, Fructose, Galactose

Question 12

Examples of disaccharides

Answer 12

Maltose, Sucrose, Lactose

Question 13

How is Maltose, Sucrose, Lactose formed

Answer 13

Glucose + Glucose = Maltose
Glucose + Galactose = Lactose
Glucose + Fructose = `sucrose

All contain glycosidic Bonds
All contain CHO
Glucose = C6H12O6

Question 14

Test for Sugar

Answer 14

1) Heat sample with Benedict’s reagent
2) If forms Brick red ppt
3) Reducing sugar

Question 15

Test for non-reducing sugar

Answer 15

If stays blue

1) Heat sample with dilute HCl
2) Neutralise with alkali
3) Heat sample again with Benedict’s reagent
4) Red colour means non-reducing sugar present

if blue twice no sugar present

Question 16

Test for stach

Answer 16

Test sample with Potassium Iodide
Brown indicates no starch
Blue indicates starch present

Question 17

Carbohydrate - starch

Answer 17

Contains glycosidic Bonds
Storage molecule in plants
Insoluble
2 types - Amylopectin and Amylose
Polysaccharide

Question 18

Carbohydrate - Cellulose

Answer 18

Condensation of beta glucose
Straight cellulose chains linked with H bonds forming micro/fibrils
Insoluble
Polysaccharide

Question 19

Carbohydrate - Glycogen

Answer 19

Animals store excess glucose as glycogen
Condensation reaction
Forms glycosidic bonds
Alpha Glucose
Side branches for quick release
Compact as storage molecule

Question 20

Proteins

Answer 20

Monomer - 1 amino acid
Dipeptide - 2 amino acid
Polypeptide - 3 or more amino acids
Protein - 1 or more Polypeptide

All contain peptide bonds

Question 21

Amino Acid Structure

Answer 21

R - variable group
N H2 - amino group
COOH - carboxyl group

Question 22

Test for Protein

Answer 22

Test solution with NaOH and CuSO4
Blue indicates no protein
Purple indicates protein present

Question 23

Lipids

Answer 23

Not polymer as has different components
Create Triglyceride and Phospholipid

Question 24

Saturated and Unsaturated

Answer 24

S - Single - Saturated
Un S - Not single - Unsaturated

Question 25

Triglyceride

Answer 25

1 Glycerol and 3 fatty acids Ester bonds between Glycerol and Fatty acid Condensation reaction Insoluble

Question 26

Fatty Acid structure

Answer 26

Cn H2n O2 HO-C=O | R

Question 27

Phospholipid

Answer 27

1 Glycerol 2 Fatty acids 1 phosphate group Creates Cell Membranes Phosphate head - hydrophilic Fatty Acid tails - Hydrophobic Heads on outside - Tails point in

Question 28

Lipid Test

Answer 28

Add ethanol Shake Add water Shake White cloudy emulsion indicates lipid present