SB6d Transpiration and translocation

Question 1

What do xylem vessels do?

Answer 1

carry water throughout the plant. As the water vapour diffuses out of a leaf, ​more moves into the ​leaf to replace it

Question 2

What are a few adaptations of xylem vessels?

Answer 2

.no cytoplasm - water can flow easily
.no cell walls - water flow is not slowed down
.thick walls - will not burst

Question 3

What do lignified dead cells in xylem do?

Answer 3

transport water and minerals through the plant

Question 4

What is sucrose translocated in?

Answer 4

sieve tubes and phloem tissue

Question 5

What do companion cells do?

Answer 5

pump sucrose into sieve tubes, increased pressure causes the sucrose solution to flow up to shoots or down to storage organs

Question 6

Transpiration?

Answer 6

the flow of water in a root, up the stem and out of the leaves

Question 7

Describe how sucrose is transported around the plant by translocation - leaf?

Answer 7

active transport leads solutes (sucrose) from companion cells into the sieve tubes, water enters the sieve tubes via osmosis, creating high pressure

Question 8

Describe how sucrose is transported around the plant by translocation - sink?

Answer 8

solutes are removed from the phloem to be used

Question 9

Describe how sucrose is transported around the plant by translocation - flow?

Answer 9

the gradient pushes solutes towards the sink, used in respiration or stored (starch)

Question 10

Factors that increase transpiration rate?

Answer 10

.wind
.higher temperature
.low humidity
.greater light intensity

Question 11

Potometer?

Answer 11

measures the rate of transpiration in mm/min

Question 12

In an experiment with a potometer, a faster wind speed causes the air bubble to move more quickly than a slower wind speed. Explain this observation.

Answer 12

Wind moves water​ molecules away from​ the stomata so water​ is taken into the plant​ and moved along the ​transpiration stream