Topic E- Respiration And Photosynthesis

Question 1

What is the word equation for anaerobic respiration in animals?

Answer 1

Glucose →lactic acid + ( energy)

Question 2

What is the word equation for aerobic respiration?

Answer 2

Glucose+oxygen→ carbon dioxide+water+( energy)

Question 2

What is the balanced chemical equation for photosynthesis?

Answer 2

6CO₂+ 6H₂O ( sunlight + chlorophyll) → C₆H₁₂O₆+6O₂

Question 2

How can varying the temperature affect the rate of photosynthesis?

Answer 2

If it gets too cold, the rate of photosynthesis will decrease. Plants cannot photosynthesise if it gets too hot.

Question 3

Why do plant need mineral ions?

Answer 3

For Growth

Question 4

What is the purpose of stomata?

Answer 4

To allows sufficient CO₂ to enter the leaf to optimize photosynthesis, while conserving as much water as possible.

Question 5

What is photosynthesis?

Answer 5

The process is the chemical change which happens in the leaves of green plants. During the reaction carbon dioxide and water are converted into glucose and oxygen. The reaction requires light energy, which is absorbed by a green substance called chlorophyll.

Question 6

Why do plants need nitrate ions?

Answer 6

For amino acids

Question 8

How can varying carbon dioxide concentration affect the rate of photosynthesis?

Answer 8

Even when there is plenty of light, a plant can not photosynthesis if there is insufficient carbon dioxide

Question 9

What’s the word equation for photosynthesis?

Answer 9

Carbon dioxide+ water (light energy+ chlorophyll) →glucose+ oxygen

Question 10

What is aerobic respiration?

Answer 10

Aerobic respiration requires oxygen. It happens in cells when glucose reacts with oxygen.

Question 11

Describe a way to work out the rate of photosynthesis

Answer 11

Collecting the volume of oxygen gas from a plant

Question 12

How is the structure of the leaf adapted for gas exchange?

Answer 12

Adaption: Internal air spaces in spongy mesophyll layer

Purpose: Increases surface area of leaf to absorb more carbon dioxide

Adaption: Guard cells around stomata

Purpose: Allows the size of stomata to be adjusted ( eg they close the stomata to prevent wilting)

Question 13

What is the symbol equation for aerobic respiration?

Answer 13

C₆H₁₂O₆+6O₂ →6CO₂+ 6H₂O+ energy

Question 14

Explain gas exchange in a leaf in relation to respiration and photosynthesis

Answer 14

CO₂ and O₂ diffuse in and out of leaves through stomata. CO₂ is used in photosynthesis and produces in respiration, whereas O₂ is used in respiration and produced in photosynthesis

Question 16

What is anaerobic respiration?

Answer 16

Anaerobic respiration does not need oxygen. It happens when there is not enough oxygen for aerobic respiration. Much less energy is released than by aerobic respiration.

Question 17

How can varying light intensity affect the rate of photosynthesis?

Answer 17

Without light plant cannot photosynthesise very quickly, even when there is plenty of water and carbon dioxide. Increasing the light intensity will boost the speed of photosynthesis.

Question 18

What’s respiration?

Answer 18

A process in living organisms involving the production of energy, typically with the intake of oxygen and the release of carbon dioxide

Question 19

Where does photosynthesis take place?

Answer 19

In the leaf cells. These contain chloroplast, which are tiny objects containing chlorophyll.

Question 20

Why do plants need magnesium ions?

Answer 20

For chlorophyll

Question 21

What is the word equation for anaerobic respiration in plants?

Answer 21

Glucose →ethanol+carbon dioxide+ ( energy released)

Question 22

Describe the iodine test

Answer 22

We use iodine solution to test for starch, which plants produce by photosynthesis

Positive: you quickly get dark purple, black color if you mix iodine solution and starch

Negative: a yellow, orange or brown colour means there is no starch

Question 23

How is a leaf adapted for photosynthesis? Give an adaption and purpose.

Answer 23

Large surface area: to absorb more light

Thin: short distance for carbon dioxide to defuse in leaf cells

Chlorophyll: absorbs sunlight to transfer energy into chemicals

Network of veins: to support the leaf and transport carbohydrates

Stomata: allow carbon dioxide to defuse into the leaf