Photosynthesis

Where does photosynthesis mainly occur in plants?

• leaves

• roots

• flowers

• stem

Why is sunlight important for photosynthesis?

In photosynthesis, plants use sunlight, water, and ________ to produce glucose and oxygen.

Draw a diagram of a plant cell

Photosynthesis occurs in the mitochondria of plant cells.

• True
• False

Answer explanation

Photosynthesis occurs in the chloroplasts, not the mitochondria.

During photosynthesis, plants take in carbon dioxide through tiny openings in their leaves called

Which of the following is NOT needed for photosynthesis

• carbon dioxide

• oxygen

• water

• sunlight

Why is photosynthesis important not only for plants, but also for animals and humans?

Answer explanation

Photosynthesis is important for plants because it helps them make their own food using sunlight, carbon dioxide, and water. It is also important for animals and humans because it produces oxygen, which we need to breathe. In addition, the food chain starts with plants, so without photosynthesis, there would be no food for herbivores and then for carnivores.

What happens to the rate of photosynthesis when the light intensity is too low?

• Stays the same

• Increases

• Becomes more efficient

• Decreases

Study the diagram carefully. In which set-up A, B, C or D will there be the least amount of carbon dioxide after several hours?

• A

• B

• C

• D