Chapter 3: Biological molecules

Question 1

What is a polar molecule?

Answer 1

A molecule that has one end slightly positive and the other slightly negative.

Question 2

Effects hydrogen bonding has on water?

Answer 2

Higher melting and boiling points, higher surface tension and good solvent

Question 3

What is thermoregulation?

Answer 3

The body cooling itself down by using water to release sweat from glands

Question 4

Cohesion definition?

Answer 4

Attraction between water molecules

Question 5

Uses of water?

Answer 5

Temperature regulation, maintains cell shape and size, prevents drying up, transports substances around body

Question 6

Thermal stability?

Answer 6

Heat disrupts the hydrogen bonds so water remains a liquid at large range of temperatures

Question 7

Carbohydrates uses?

Answer 7

Storage, cellulose and respiration

Question 8

Carbohydrates test?

Answer 8

Benedicts solution. Originally blue.
Partial positive = yellowy-orange
Strong positive = Brick red

Question 9

Monosaccharides?

Answer 9

Simple sugars e.g. glucose, fructose
Sweet, soluble in water and form crystals

Question 10

Glucose properties?

Answer 10

Building block for large carbohydrates, lots of bonds and good energy source for respiration.
Hexose monosaccharide

Question 11

Disaccharides?

Answer 11

Made up of 2 monosaccharides, linked with glycosidic bond. Example = maltose

Question 12

Maltose?

Answer 12

Two alpha glucose bonded together with a condensation reaction. C1 and C4 bond together

Question 13

Uses of lipids?

Answer 13

Insulation, buoyancy in aquatic animals, source and storage of energy, cushioning, solvent and waterproofing

Question 14

Difference between unsaturated and saturated lipids?

Answer 14

Unsaturated have carbon double bonds (often liquid at room temp) and saturated don’t have carbon double bonds

Question 15

What are Triglycerides?

Answer 15

Lipids that circulate in your blood. Contain glycerol and fatty acids

Question 16

How does a fatty acid and a glycerol join?

Answer 16

Esterification, it forms 3 ester bonds

Question 17

What are phospholipids made up of?

Answer 17

ONLY 2 ESTER BONDS. Phosphate head which is hydrophilic, glycerol and a hydrophobic fatty acid tail

Question 18

Structure of cholesterol?

Answer 18

4 carbon based ring structure

Question 19

Function of cholesterol?

Answer 19

Regulates fluidity of plasma membrane. Also makes hormones like oestrogen and testosterone

Question 20

What happens when you have a Vitamin D deficiency?

Answer 20

Rickets or ‘bendy bones’

Question 21

What are gall stones?

Answer 21

Hard deposits of cholesterol. Stops bile leaving the gall bladder

Question 22

Bad cholesterol effect?

Answer 22

Builds up plaque in your arteries which increases risk of heart disease

Question 23

What molecules make up a protein?

Answer 23

Carbon, hydrogen, oxygen, sulphur and nitrogen

Question 24

Formula for a disaccharide?

Answer 24

C12 H22 O11

Question 25

What makes up sucrose?

Answer 25

Fructose and glucose. It is a non reducing sugar

Question 26

What makes up lactose?

Answer 26

Galactose and glucose

Question 27

Amylose properties?

Answer 27

From a plant. Made of alpha glucose. Uses 1-4 glycosidic bonds and doesn’t branch

Question 28

Amylopectin properties?

Answer 28

From a plant. Made of alpha glucose. Uses 1-4 and 1-6 glycosidic bonds and does branch every 20 subunits

Question 29

Cellulose properties?

Answer 29

From a plant. Made of beta glucose. Uses 1-4 glycosidic bonds and doesn’t branch off

Question 30

Glycogen properties?

Answer 30

From an animal. Made of alpha glucose. Uses 1-4 and 1-6 glycosidic bonds. Branches off every 10 subunits

Question 31

What is a hydrolysis reaction?

Answer 31

To release glucose for respiration, starch and glycogen undergo a hydrolysis reaction. Requiring the addition of water molecules.