1. Water Carbs & Proteins

Question 1

As a frozen lake warms after a cold winter, mineral nutrients are brought to the surface.
Which properties of water contribute to this process? 2

Answer 1

It’s greatest density is at 4°C

It is a Solvent

Question 2

When a lake begins to freeze, which properties of water are needed for fish to survive? (2)

Answer 2

Water has a high thermal capacity.

Water has its maximum density at 4 °C

Question 3

Reagent and positive result in testing for starch

Answer 3

Iodine solution
Blue/black colour

Question 4

Reagent and positive result in testing for reducing sugars

Answer 4

Benedict’s reagent
green/yellow/orange/red colour

Question 5

Reagent and positive result in testing for non-reducing sugars

Answer 5

Boil with Benedict’s reagent after acid hydrolysis

darker colour

Question 6

What type of sugar is glucose?

Answer 6

reducing sugar

Question 7

What type of sugar is sucrose?

Answer 7

non-reducing sugar

Question 8

What is alpha glucose found in? 3

Answer 8

glycogen
amylopectin
amylose

Question 9

What is Beta glucose found in?

Answer 9

cellulose

Question 10

Draw a diagram of β glucose

Answer 10

5 A

Question 11

Which features adapt cellulose molecule for its function? (2)

Answer 11

1. Many hydrogen bonds form between adjacent chains
2. insoluble in water

Question 12

What is a glycosidic bond

Answer 12

Bond that forms between sugar molecules to form carbs

Question 13

draw a diagram of alpha glucose

Answer 13

Y question 4

Question 14

Which molecular bonds will be broken by hydrolysis when a molecule of glycogen is converted to glucose? 2

Answer 14

1,4 and 1,6

Question 15

What is a polymer?

Answer 15

Giant molecule made from monomers

Question 16

What is a macromolecule and examples 4

Answer 16

large biological molecule
eg.
-protein
-polysaccharides
-nucleic acid

Question 17

What is a disaccharide with examples 3

Answer 17

Two monosaccharides joined together
-sucrose
-maltose

Question 18

Features of cellulose 7

Answer 18

-main component of cell walls
-very strong bc of how it’s banded
-made from beta glucose
-beta glucose causes alternating structure that makes it strong
-Oxygen in OH groups attracted to Oxy in glucose ring and OH groups of neighboring molecules
-allows formation of hydrogen bonds
-hydrogen bonding forms microfibrils

Question 19

Which groups form peptide bonds on amino acid?

Answer 19

Carboxylic (COOH) and amine (NH2) groups

Question 20

why is haemoglobin able to carry oxygen?

Answer 20

It contains iron

Question 21

features of haemoglobin 4

Answer 21

-4 polypeptide chains, each containing 1 prosthetic group

-iron ions can associate with oxygen & form oxyhaemoglobin

-in each chain, hydrophobic R groups of amino acids point towards the centre of the molecule

-at 50 % saturation, two oxygen molecules are transported by the molecule

Question 22

Polypeptide bond is formed between which 2 elements

Answer 22

carbon and nitrogen

Question 23

Which features affect the tensile strength of collagen? 5

Answer 23

-the helical structure of collagen chains
- small R group of amino acids in collagen
-the covalent bonds between collagen molecules
-lots of glycine
-peptides close to eachother

Question 24

Composition of haemoglobin with oxygen

Answer 24

4 haem groups
4 oxygen molecules
8 oxygen atoms

Question 25

What is the strongest protein bond?

Answer 25

covalent bond

Question 26

Describe hydrogen bonds IN PROTEINS 3

Answer 26

-form between polar R groups
-polar groups e.g NH, CO, OH
-weak on their own but strong in numbers

Question 27

describe disulphide bonds 3

Answer 27

-broken by reducing agents
-Form between cystein R groups
-strong covalent bond

Question 28

Define water density 2

Answer 28

Weight of water per unit of volume

depends on temperature

Question 29

What is thermal capacity?

Answer 29

the quantity of heat necessary to produce a unit change of temperature in a unit mass of a material.

Question 30

When red blood cells leave the lungs, they’re 98% saturated

How many molecules of oxygen will be carried by majority of haemoglobin molecules?

Answer 30

4