Nutrition

Question 1

Explain the process of photosynthesis including the equation.

Answer 1

Photosynthesis is the process where green plants make carbohydrates from carbon dioxide and water using light energy absorbed in chlorophyll. This process takes place in the chloroplast. Oxygen is released as a by product. This process takes place in 2 stages:
Light stage where chlorophyll traps light energy which is used to split water molecule into oxygen and hydrogen. The oxygen is extreted as it diffuses out of the leaf.
Dark stage is when the hydrogen reduces carbon dioxide to form C⁶H¹²O⁶.
The equation for this process is
6CO² + 6H²O–> C⁶H¹²O⁶.

Question 2

Identify 2 parts of a food is stored in a flowering plant.

Answer 2

Leaves and roots

Question 3

Name 3 nutrition in plant storage organs that humans use as food.

Answer 3

Fats in seeds, water in roots and fibre in leaves

Question 4

Describe the test for starch in leaves in a laboratory.

Answer 4

A leaf is placed in boiling water which kills the cells to ensure the starch present isn’t used up. The leaf is then removed and placed into ethanol which removes chlorophyll. Lastly it is removed and drops of iodine is placed on the leaf turing the leaf blue black. This indicates starch is present.

Question 5

What method is used to test for protein and state the observation made.

Answer 5

KOH followed by CuSO⁴ is added turing plant blue to purple. This indicates protein is present.

Question 6

Where is food stores in animals?

Answer 6

In animals food is stored in the liver, under skin and around organs.

Question 7

State 2 adaptations for photosynthesis.

Answer 7

Leaves lie at 90° and are spaced out around the steam to trap sunlight.
Xylem that carries water to the leaf cells.

Question 8

What are the factors affecting photosynthesis?

Answer 8

Temperature, water, light intensity and carbon dioxide concentration.

Question 9

What is mechanical and chemical digestion?

Answer 9

Mechanical digestion involves breaking up large pieces of food into small pieces. It begins in the mouth and carried out by the teeth.
Chemical digestion involves breaking down large insoluble food into small soluble food molecules. It begins in mouth, continues in stomach and is completely in small intestine

Question 10

What are the final products of starch, protein and fats in the digestive system?

Answer 10

Starch- glucose
Protein- amino acids
Fats- fatty acid+ glycerol