Biology Ka2

Question 1

What are chloroplasts?

Answer 1

Green discs that allow the plant to make food by photosynthesis

Question 2

What do the roots of a plant do?

Answer 2

Take up water and minerals, keeps the plant

Question 3

What are the different leaf adaptations?

Answer 3

• large surface area for absorbing light
• contain chlorophyll and chloroplasts to absorb light energy
• Air spaces to allow CO₂ to get to the cells and oxygen to leave them by diffusion
• veins to bring water to leaf cells

Question 4

What is the function of a root hair cell?

Answer 4

Absorb water

Question 5

What is the function of the xylem vessels?

Answer 5

They transports water

Question 6

Name two uses of water

Answer 6

Photosynthesis and keeps the plant the rigid

Question 7

Name do jobs of the stem

Answer 7

• support leaves

* Carry water to leaves

Question 8

Which plant organ does water leave from?

Answer 8

The leaves

Question 9

What do plants need for photosynthesis?

Answer 9

Carbon dioxide and water

Question 10

How does the stomata help with gas exchange?

Answer 10

Small holes on the under side of the leaf that open and close to allow air into the leaf spaces

Question 11

What is algae?

Answer 11

Algae are aquatic organisms that are adapted to photosynthesise in water by absorbing CO₂ dissolved in the water around them

Question 12

Why do all organisms need food?

Answer 12

For respiration, growth and reproduction

Question 13

Which part of the plant does photosynthesis happen in?

Answer 13

The leaves

Question 14

How to plants photosynthesise?

Answer 14

Energy is transferred from the environment to the chloroplasts by light, it is then transferred to convert Co₂ from the air, plus water from the soil into a sugar called glucose, oxygen is released as a by product for us to breathe

Question 15

Why is photosynthesis an endothermic reaction?

Answer 15

Because it needs an input of energy from the environment

Question 16

What is the word equation for photosynthesis?

Answer 16

Carbon dioxide + water –> glucose + oxygen

Question 17

What is the chemical equation for photosynthesis?

Answer 17

6Co₂ + 6H₂O –> C₆H₁₂O₆ + 6O₂

Question 18

What happens to the energy transferred from the environment?

Answer 18

The energy transferred from the environment when the bonds holding CO₂ and H₂O together are broken. The energy transferred back to the environment with the formation of new bonds in glucose and oxygen

Question 19

What do all of the leaf adaptations do?

Answer 19

Allow maximum amount of the photosynthesis to take place

Question 20

Carbon dioxide joins with _____ to make ______ and _______

Answer 20

Water, glucose, oxygen

Question 21

Why do plants grow faster in the summer?

Answer 21

Because they need warmth and CO₂ if they are going to photosynthesise and grow

Question 22

What factors affect the rate of photosynthesis?

Answer 22

Light, temperature and carbon dioxide concentration

Question 23

How does light effect the rate of photosynthesis?

Answer 23

The more light the more a plant can photosynthesise and grow faster

Question 24

How does temperature effect the rate of photosynthesis?

Answer 24

As the temperature rises, the rate of photosynthesis increases. Photosynthesis is controlled by enzymes. Most are denatured at around 40-50’c. If the temperature is too high, the rate of photosynthesis will decrease

Question 25

How does carbon dioxide level effect the rate of photosynthesis?

Answer 25

Plants need CO₂ to make glucose. The atmosphere is only 0.04% CO₂ which limits the rate of photosynthesis.

Question 26

What happens if the chlorophyll in a leaf is limited?

Answer 26

Less photosynthesis will take place

Question 27

How do plants help us live? W

Answer 27

Photosynthesis puts oxygen into the atmosphere for us to live on

Question 28

What do plants make?

Answer 28

Complicated molecules such as carbohydrates, fats and proteins. They also make simple molecules such as CO₂ and H₂O using energy from the sun