Biological Molecules

Question 1

What are the chemical element present in carbohydrates?

Answer 1

Carbon, hydrogen, oxygen

Question 2

What are the chemical element present in Proteins?

Answer 2

Carbon, hydrogen, oxygen and nitrogen

Question 3

What are the chemical elements present in lipids?

Answer 3

Carbon, hydrogen, and oxygen

Question 4

The structure of carbohydrates

Answer 4

Large molecules, starch and glucose from simple sugar

Question 5

The structure of protein

Answer 5

Large molecules, made up of amino acids

Question 6

The structure of lipids

Answer 6

Large molecules, made up of fatty acids and glycerol

Question 7

Test for glucose

Answer 7

Benedict’s test. The test involves heating the sugar with either of the chemicals and observing the colour change of blue to orange

Question 8

Test for starch

Answer 8

Iodine solution and see if it turns from red to blue/black in colour

Question 9

What is the role of enzymes as biological catalysts in metabolic reactions?

Answer 9

Enzymes lower the activation energy of a reaction- making it faster- and they are unchanged from begining to end of a reaction.

Question 10

Describe an experiment illustrating how enzymes activity can be affected by temperature

Answer 10

Put starch into a test tube; heat it,
Add amylase,
With this mixture on white tiles, add iodine,
Time how long it takes for the iodine to stop being blue black,
Repeat at different temperatures and compare them

Question 11

Describe an experiment illustrating how enzymes activity can be affected by pH levels

Answer 11

Several test tubes were filled with different pH levels of starch solutions. Then the same amount of amylase were added to each tube and immediately, one drop of each mixture was put on the white tile and a drop of I2KI was added. This was repeated at one minute intervals. After 8 minutes, add 5 drops of Benedict’s solution to the test tubes.