(i)

Conditions that are required for photosynthesis to take place

1. Presence of sunlight/light
2. Presence of carbon dioxide
3. Presence of chlorophyll
4. Suitable temperature/warmth
5. Water/mineral salts

(ii)

How to show that starch is formed during photosynthesis

1. Two leaves are plucked, one from a plant exposed to sunlight for at least two hours and the other from plant kept in the dark for the same period
2. Both leaves are boiled in water to kill the cells
3. Both leaves are boiled in alcohol to remove pigmentation/chlorophyll
4. Both decolourized leaves are washed in warm water to soften them
5. Dip both leaves in iodine solution
6. The leaf plucked from plant in the sunlight turns blue black with iodine showing the formation of starch during photosynthesis
7. The leaf plucked from plant kept in the dark remains colourless showing there was no formation of starch because photosynthesis did not take place

i)

Photosynthesis is a process whereby green plants containing chlorophyll manufacture food/carbohydrates/starch/glucose from carbon dioxide and water in the presence of sunlight.

ii)

Importance of photosynthesis to animals

1. Food/carbohydrates/starch/glucose produced provides energy for animals
2. Oxygen released is used for respiration
3. Accumulation of carbon dioxide is prevented since they are used by plants during photosynthesis

(α)

Function of chlorophyll in photosynthesis

Absorbs/traps sunlight/converts CO₂ and H₂O into glucose

(β)

Function of water in photosynthesis

Used to produce glucose/produces oxygen

i)

Factors necessary for photosynthesis

1. Sunlight
2. Chlorophyll
3. Carbon dioxide
4. Water

ii)

Function of sunlight

Is to separate the hydrogen and oxygen atoms of water/provides energy

Functions of chlorophyll

Absorbs/traps light

Function of water

Splits into oxygen, hydrogen ions and electrons to replace the lost electrons/raw material/combines with CO₂ to produce food

Function of carbon dioxide

It's a raw material/used in splitting water/is reduced to sugar

(i)

The process by which green plants manufacture their food is called photosynthesis

(ii)

Factors necessary for photosynthesis

1. Chlorophyll/green matter in the leaf
2. Sunlight/light
3. Water (H₂O)
4. Mineral salts
5. Carbon dioxide/Carbon (IV) oxide/ (CO₂)
6. Suitable temperature