6. Plant nutrition

Question 1

What are 5 different forms which carbohydrates made in photosynthesis are stored?

Answer 1

starch, cellulose, glucose, sucrose, nectar

Question 2

What is the use of starch?

Answer 2

stores energy

Question 3

What is the use of cellulose?

Answer 3

builds cell walls

Question 4

What is the use of glucose?

Answer 4

for respiration (provides energy)

Question 5

What is the use of sucrose?

Answer 5

to be transported in phloem vessels

Question 6

What is the use of nectar?

Answer 6

it attracts insects for pollination

Question 7

Why are nitrate ions important for plants?

Answer 7

produce amino acids

Question 8

Why are magnesium ions important for plants?

Answer 8

make chlorophyll

Question 9

What is the effect of concentration of Co2 on photosynthesis?

Answer 9

when level increases, so does rate of photosynthesis since co2 is necessary to carry out photosynthesis. however, there will reach a point in which it will make no difference anymore because there is another limiting factor, possibly the number of chloroplasts in the leaf, light intensity, temperature…

Question 10

What is the effect of light on photosynthesis?

Answer 10

when level increases, so does rate of photosynthesis since light is necessary to carry out photosynthesis. however, there will reach a point in which it will make no difference anymore because there is another limiting factor, possibly the number of chloroplasts in the leaf, CO2 concentration, temperature…

Question 11

What is the effect of temperature on photosynthesis?

Answer 11

when level increases, so does rate of photosynthesis since molecules have more energy at higher temperatures. however, there will reach a point, after optimum temperature, in which enzymes will denature and not function anymore, reducing rate of photosynthesis.

Question 12

Define ‘photosynthesis’.

Answer 12

process which plants use energy from light to synthesise carbohydrates from raw materials

Question 13

State the word equation for photosynthesis.

Answer 13

carbon dioxide + water → glucose + oxygen

Question 14

What other two things does photosynthesis need to occur?

Answer 14

light and chlorophyll

Question 15

What is chlorophyll?

Answer 15

green pigment in chloroplasts

Question 16

What is the role of chlorophyll in photosynthesis?

Answer 16

converts light energy into chemical energy, for the synthesis of carbohydrates to occur

Question 17

State the balanced chemical equation of photosynthesis.

Answer 17

6CO2 + 6H2O → C6H12O6 + 6O2

Question 18

What are two adaptations of leaves that help them in their functions?

Answer 18

large surface area
thin

Question 19

Name two reasons why leaves are thin.

Answer 19

• CO2 from the air can quickly diffuse to cells which perform photosynthesis
• sunlight can penetrate more easily

Question 20

Name a reason why leaves have large surface areas.

Answer 20

• large area exposed to sunlight/air (can absorb more easily)

Question 21

How is the cuticle adapted for its function?

Answer 21

waxy layer

Question 22

you are doing

Answer 22

great (bjs - annuca)

Question 23

How are the upper/lower epidermis adapted for their function (except for guard cells)?

Answer 23

very thin layer, no chloroplasts, allows light to penetrate

Question 24

How is the palisade mesophyll layer adapted for its function?

Answer 24

• many chloroplasts
• chloroplasts at edge of the cell for a large vacuole allowing more light to enter

Question 25

How is the xylem adapted for its function?

Answer 25

made of dead cells: tubes are hollow and waterproof, allowing water to pass

Question 26

How is the phloem adapted for its function?

Answer 26

sieve tubes for the transportation of sucrose
companion cells so that energy for transport is provided

Question 27

How is a guard cell adapted for its function?

Answer 27

gain and lose water, causing them to change shape and open and close the stoma

Question 28

How is the spongy mesophyll adapted for its function?

Answer 28

air spaces between cells, making diffusion of gases throughout the leaf possible

Question 29

What is the function of the cuticle?

Answer 29

prevents water loss by evaporation from leaf

Question 30

What is the function of the chloroplast?

Answer 30

photosynthesis occurs here

Question 31

What is the function of the upper epidermis?

Answer 31

protects inner cells

Question 31

What are the functions of the upper/lower epidermis?

Answer 31

protects inner cells

Question 32

What is the function of the palisade mesophyll layer?

Answer 32

photosynthesis occurs here

Question 33

What is the function of the xylem?

Answer 33

transports water + mineral ions from roots to leaves

Question 34

What is the function of the phloem?

Answer 34

transports sucrose away from leaf

Question 35

What is the function of the guard cell?

Answer 35

in pairs, to control the size of a stoma’s opening

Question 36

What is the function of the stomata?

Answer 36

it controls the diffusion of gases in and out of the leaf

Question 37

What is the function of the air spaces?

Answer 37

leave space for diffusion of gases throughout leaf