Plant Structures

Question 1

All living things need g______ to respire and release energy to live

Answer 1

Glucose

Question 2

All food chains start with plants which photosynthesise to make glucose. These are p______

Answer 2

Producers

Question 3

What is biomass?

Answer 3

All the material in an organism

Question 4

Where does all biomass come from?

Answer 4

The producers

Question 5

What is the photosynthesis equation?

Answer 5

Carbon dioxide+water—>glucose+oxygen

Question 6

How is sunlight absorbed for photosynthesis?

Answer 6

The chlorophyll found in the leaves

Question 7

What else can glucose be stored as?

Answer 7

Starch

Question 8

What is an endothermic reaction?

Answer 8

A chemical reaction where the products have more energy than the reactants

Question 9

Why is photosynthesis endothermic?

Answer 9

Because glucose and oxygen have more energy than carbon dioxide and water

Question 10

How do root hair cell take in minerals and water?

Answer 10

• water enters via osmosis

- minerals taken up by active transport

Question 11

How are root hair cells adapted to their function?

Answer 11

‘Hairs’ provide a large surface are for the water and mineral intake

Thin cell wall for a short path for water and minerals

Many mitochondria, providing energy for active transport

Question 12

What is the difference in concentration of mineral ions in the cell than the soil?

Answer 12

Concentration of mineral ions is usually higher in the cells than the soil around them

Question 13

What is a ‘limiting factor’?

Answer 13

Something that affects the rate of photosynthesis

Question 14

What are the 3 limiting factors?

Answer 14

Light intensity

Carbon dioxide concentration

Temperature

Question 15

What does the waxy cuticle of the leaf cell do?

Answer 15

Reduces water loss

Question 16

What do palisade cells do?

Answer 16

Many chloroplasts for maximum photosynthesis

Question 17

What does the spongy layer do?

Answer 17

Air gaps for carbon dioxide and oxygen to diffuse through the leaf

Question 18

What do guard cells do?

Answer 18

Open and close the stomata

Question 19

What does the stomata do?

Answer 19

Pores to allow gas exchange

• open in the day for CO2 for photosynthesis (water leaves)
• close at night to prevent water loss and wilting

Question 20

What is transpiration?

Answer 20

Water moves up a plant in the xylem vessels and evaporates out through the stomata

Question 21

What are the 5 steps of transpiration?

Answer 21

1. Water enters root hair cells via osmosis
2. Water enters bottom of xylem vessels from the root by osmosis
3. Water is pulled up the xylem vessels
4. Water enters the leaf cells by osmosis
5. Water evaporates through stomata

Question 22

What can be used to estimate the rate of transpiration?

Answer 22

Potometer

Question 23

What is the equation for transpiration?

Answer 23

Distance bubble moves/time

mm/min

Question 24

How and why does light affect the rate of transpiration?

Answer 24

In bright light, transpiration increases

Because more stomata open (more CO2 in)

Question 25

How and why does temperature affect the rate of transpiration?

Answer 25

Transpiration is faster in higher temperatures Evaporation and diffusion take place at a faster rate

Question 26

How and why does wind affect the rate of transpiration?

Answer 26

Transpiration is faster in windy conditions Water vapour is removed faster keeping concentration gradient steep

Question 27

Why are xylem vessels long tubes with no ends?

Answer 27

Because ends would slow the water down

Question 28

Why do xylem vessels contain lignin?

Answer 28

Makes walls strong prevents collapse of xylem under pressure

Question 29

Why are xylem vessels dead cells with no nucleus and little cytoplasm?

Answer 29

Dead cells - no energy is wasted No nucleus + little cytoplasm - space for water to flow

Question 30

Why do xylem vessels have tiny pores in the walls?

Answer 30

Allows water to move in and out

Question 31

What is translocation?

Answer 31

When glucose is converted into sucrose an moves up and down the plant in the phloem tissue

Question 32

What are the 2 parts of the phloem tissue and what do they do?

Answer 32

Companion cells - actively load sucrose into the sieve tubes Sieve tubes - translocate sucrose up and down the stem

Question 33

Why does the phloem tissue contain living cells?

Answer 33

So the cell can have active processes

Question 34

Why do companion cells contain lots of mitochondria?

Answer 34

Cells can respire and release energy to actively load sucrose into sieve tubes

Question 35

Why are there pores between the companion cells and the sieve tubes?

Answer 35

Allows sucrose to be actively loaded