Plant transport, storage and gas exchange

Question 1

Plants make their own food meaning they are

Answer 1

Autotrophic

Question 2

Plants transport

Answer 2

Water, Carbon dioxide, oxygen, minerals and plant growth regulators for metabolism

Question 3

Why is water needed

Answer 3

Photosynthesis, cell metabolism, growth and cell turgidity

Question 4

Water uptake by roots

Answer 4

1. Water is absorbed by root hairs by osmosis
2. Water enters the cytoplasm
3. Water moves from cell to cell by osmosis

Question 5

How are root hairs adapted

Answer 5

1. Provide a large surface area
2. No cuticle
3. Have thin walls

Question 6

What is the transport of water caused by

Answer 6

1. Root pressure

2. Transpiration

Question 7

Root pressure

Answer 7

forced upward movement of water and minerals from the root to stem

Question 8

Transpiration

Answer 8

Loss of water vapour from a plant through stomata

Question 9

Cohesion-Tension theory

Answer 9

1. Water evaporates at the leaf in transpiration
2. Loss of water creates tension
3. Tension pulls water up as a continuous stream creating a transpiration stream
4. Water molecules are attracted to each other in a process called cohesion
5. Water molecules are attracted to the xylem in a process called adhesion
6. Root pressure is a force generated by the root, as water is absorbed, it pushes water up the stem

Question 10

Name 2 scientists associated with the cohesion-tension model of transport

Answer 10

• Dixon

- Joly

Question 11

Mineral uptake and transport

Answer 11

• Minerals are absorbed into the root hairs by active transport
• Passed through xylem and carried up the stem
• Root hair cells are adapted as mitochondria supplies energy
• Minerals needed are calcium(forms middle lamella) and magnesium (produce chlorophyll)

Question 12

Carbon dioxide uptake and transport

Answer 12

• CO2 diffuses in through the stomata of the leaf from the atmosphere
• Respiration in plant cells provides CO2 to the plant
• CO2 diffuses through the air spaces in the leaf to the ground tissue or mesophyll cells

Question 13

Transport and Oxygen

Answer 13

• O2 is a product of photosynthesis

- Some O2 is used in plant respiration and excess O2 diffuses into the atmosphere through the stomata

Question 14

Transport of the photosynthetic product glucose

Answer 14

• Translocated as sucrose in phloem sieve tubes

- Sucrose is the main transport carbohydrate in phloem

Question 15

Transport of growth regulators

Answer 15

• Diffusion and active transport

Question 16

Modified root

Answer 16

• Taproot
• Carrots
• Glucose

Question 17

Modified stem

Answer 17

• Potato tuber

- Starch

Question 18

Modified leaf

Answer 18

• Bulb is an underground stem with leaves
• Onions
• Glucose

Question 19

Perennials

Answer 19

Plants that survive from one growing season to the next by storing food as starch

Question 20

Gas exchange through leaf stomata

Answer 20

• Stomata are dermal pores/openings for gas exchange
• CO2 diffuses through stomata from the atmosphere
• O2 diffuses out through stomata into the atmosphere
• Water vapour moves out from stomata called transpiration

Question 21

How is the leaf adapted

Answer 21

• A large number of stomata
• Thin
• Increase surface area

Question 22

Control of transpiration

Answer 22

• Waxy cuticle is waterproof

- Closure of stomata in times of water shortage

Question 23

Name the structures found in stems

Answer 23

Lenticels

Question 24

Name two compounds that leave the plant through the lenticels

Answer 24

• water

- oxygen

Question 25

Define lenticels

Answer 25

- Openings in the stem which allow gas exchange

Question 26

Factors that control stomatal opening and closing

Answer 26

1. Water- open when guard cells become turgid | 2. CO2- no photosynthesis at night since no light but photosynthesis resumes in the morning

Question 27

Indicate 2 ways plants use to control transpiration

Answer 27

- Waxy cuticle is waterproof | - closure of stomata

Question 28

Give 2 structural differences between Xylem and Phloem

Answer 28

- Phloem has nuclei xylem doesn't | - Xylem is a continuous tube and phloem is not

Question 29

Name the vascular tissue through which the products of photosynthesis are transported in plants

Answer 29

Phloem

Question 30

Give 2 structural features of Phloem

Answer 30

- Sieve tube | - Companion cells

Question 31

Describe the relationship between the rate of transpiration and the rate of water uptake during the day Name a reason why

Answer 31

- Water uptake and rate of transpiration increases | - More water absorption to replace the water lost

Question 32

Under what conditions does the highest rate of transpiration occur on the day

Answer 32

- Higher temperature | - Bright conditions

Question 33

Name the cells which control the opening and closing of stomata

Answer 33

Guard cells

Question 34

What is the advantage to plants having most of their stomata on the underside of the leaf

Answer 34

Reduce water loss by transpiration

Question 35

Give a disadvantage to plants of a high rate of transpiration

Answer 35

Wilting

Question 36

What do plants do in response to wilting

Answer 36

Close stomata

Question 37

Name 2 Irish scientists who proposed the theory of water movement in plants

Answer 37

Dixon and Joly

Question 38

Name the openings in the leaf which allow the entry of carbon dioxide for photosynthesis

Answer 38

Stomata

Question 39

Factors that influence the diameter of these openings

Answer 39

CO2

Question 40

Distinguish between Tuber and Bulb

Answer 40

Tuber - stem | Bulb - Leaf

Question 41

What is the function of stomata

Answer 41

Gas exchange

Question 42

Name a factor in stems equivalent to stomata

Answer 42

Lenticels

Question 43

Name a plant in which the leaves are modified for food storage

Answer 43

Onions

Question 44

Name a carbohydrate that you would expect to find in the modified leaves

Answer 44

Starch

Question 45

Name a type of modified stem that functions in food storage

Answer 45

Potato tuber

Question 46

Name a type of modified root that functions in food storage

Answer 46

Carrot