Biological molecules (2c)

Question 1

chemical elements present in carbohydrates

Answer 1

Carbon, Oxygen and hydrogen

Question 2

chemical elements present in protein

Answer 2

All contain carbon, oxygen, hydrogen and nitrogen (some other small amount of other elements such as sulphur)

Question 3

chemical elements present in lipid

Answer 3

Carbon, oxygen and hydrogen

Question 4

describe the structure of carbohydrates

Answer 4

large molecules made up from starch and glycogen from simple sugars,

Question 5

describe the structure of protein

Answer 5

Large molecules made up from amino acids

Question 6

describe the structure of lipids

Answer 6

Large molecules made up from fatty acids and glycerol

Question 7

Role of enzymes

Answer 7

act as biological catalysts to speed up the rate of all metabolic reactions

Question 8

how temperature changes can affect enzyme function

Answer 8

-When enzymes are at too low temperature (0-30) they are going to have very little kinetic energy so enzymes will not collide.
-When enzymes are at optimum temperature (body temperature(30-40)) they work as expected.
-When enzymes are at too high temperature they are going to be denatured meaning their active site is going to change of shape and is not going to work properly.

Question 9

how enzyme function can be affected by changes in pH altering the active site

Answer 9

-At the optimum pH, the enzyme is working at its fastest rate.
-At higher or lower pH’s (above or below the optimum) the enzymes are starting to become denatured and as a result are unable to bind

Question 10

Test for Glucose

Answer 10

Benedict’s solution turns from blue to brick red

Question 11

Test for starch

Answer 11

Iodine turns from orange to black

Question 12

Test for protein

Answer 12

Potassium hydroxide and copper sulphate (biuret) turns from blue to purple

Question 13

Test for fat

Answer 13

Ethanol and water solution turns from colourless to white cloudy