Chemicals Of Life

Question 1

What elements do carbohydrates contain?

Answer 1

Carbon, hydrogen, oxygen

Question 2

Glycerol is a basic unit of what

Answer 2

Oils

Question 3

What elements do fats contain

Answer 3

Carbon, hydrogen, oxygen

Question 4

What do amino acids link together to form that then links together to form proteins

Answer 4

Polypeptides

Question 5

How do you test for starch

Answer 5

Add a few drops of iodine solution to the substance being tested.
Black/blue = starch
Brown = absent

Question 6

What is simple sugar the basic unit of

Answer 6

Starch and glycogen

Question 7

What is the basic unit of proteins

Answer 7

Amino acids

Question 8

What is amino acids the basic unit of

Answer 8

Proteins

Question 9

What is fatty acids and glycerol the basic units of

Answer 9

Fats and oils

Question 10

Chemical test for reducing sugars?(maltose and glucose)

Answer 10

Add benedict’s solution, then heat mixture in water bath for 2-3 minutes at 90*C

If either sugar is present it will go red/orange/yellow/green
Blue if neither is present

Question 11

Chemical test for proteins?

Answer 11

Using biuret solutions 1 and 2. Add equal volumes of solution 1 + 2 to a solution of substance to be tested
Purple = positive
Blue = absent

Question 12

Chemical test for fats

Answer 12

Emulsion test, ethanol is added to mixture and this is poured into a test tube with an equal amount of distilled water
If positive -milky white emulsion

Question 13

Carbohydrates use

Answer 13

Energy

Question 14

Uses of proteins in body

Answer 14

energy, building materials, enzymes, haemoglobin, structural material (muscle), hormones, antibodies

Question 15

Uses of proteins

Answer 15

Source of Energy, building materials, energy store, insulation, buoyancy, making hormones

Question 16

Uses of vitamin C

Answer 16

Protect cells from ageing p, production of fibres

Question 17

Use of vitamin D

Answer 17

Absorption of calcium

Question 18

Use of iron

Answer 18

Making haemoglobin

Question 19

Uses of fibre

Answer 19

Provides bulk for faeces, helps peristalsis

Question 20

Water uses

Answer 20

Chemical reactions, solvents for transport

Question 21

Lack of vitamin C?

Answer 21

Scurvy; loss of teeth, pale skin and sunken eyes

Question 22

Lack of calcium?

Answer 22

Rickets; weak bones and teeth, poor clotting of blood, spasms

Question 23

Lack of vitamin D?

Answer 23

Rickets; weak bones and teeth

Question 24

Deficiency of iron?

Answer 24

Anaemia; fatigue(less iron–> less haemoglobin –> less oxygen transported –> less respiration –> less energy)

Question 25

What elements make up proteins?

Answer 25

Carbon, hydrogen, oxygen and nitrogen

Question 26

Test for vitamin C

Answer 26

Add solution of testing substance drop by drop to DCPIP
Result:
DCPIP changes from blue to colourless if vitamin C is present