Cells And Plants (mocks)

Question 1

Function of the roots

Answer 1

Keep the plant in the ground and take in water and nutrients from the soil

Question 2

Function of the leaves

Answer 2

Absorb sunlight, making food for the plant via photosynthesis. Site of evaporation of water.

Question 3

Function of the stem

Answer 3

Supports the leaves and flowers and transports water and nutrients between the roots and the leaves.

Question 4

2 adaptations of root hair cells

Answer 4

Long + thin, large SA

Question 5

Water passes from the soil into the root hair cell via ——

Answer 5

Osmosis.

Question 6

Minerals pass from the soil into the root hair cell via ——

Answer 6

Active transport.

Question 7

Function of the permanent vacuole

Answer 7

Filled with cell sap to keep the cell turgid

Question 8

What 2 features do all eukaryotic cells share

Answer 8

1. Contain a nucleus

2. With a distinct membrane

Question 9

Define a pathogen

Answer 9

A disease causing organism (fungi, bacteria, protoctists, viruses)

Question 10

Why does temperature increase the rate of transpiration?

Answer 10

At warmer temperatures:

• water molecules move faster
• plants need to cool down
• water holding capacity of warm air is greater than that of cold air

Question 11

Why does an increase in light intensity increase rate of transpiration?

Answer 11

• stomata open wider to allow more CO2 into the leaf for photosynthesis.

Question 12

Why does increasing wind speed increase rate of transpiration?

Answer 12

• moving air removes water vapour
• decreasing WP outside of lead
• increasing WP gradient
• increasing diffusion of water

Question 13

Why does increasing humidity decrease transpiration?

Answer 13

• causes increased WP outside leaf
• WP gradient decreases
• diffusion of water decreases

Question 14

Define transpiration

Answer 14

Evaporation of water at the surfaces of the spongy mesophyll cells followed by loss of water vapour through the stomata

Question 15

Describe transpiration

Answer 15

1. transpiration (evaporation of water through the stomata) produces a water potentially gradient. there is more water in the roots than in the leaves.
2. water moves via osmosis in the transpiration stream from a high wp in the roots to a low wp in the leaves via the xylem
3. As water moves from the roots to the leaves more moter is drawn up from the soil into the root hair cells. as the WP in saill is larger than in roots so asmosis occurs