Flashcards in Transpiration and translocation Deck (24)
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1
How does water enter plant roots?
osmosis
2
How do mineral ions enter plant roots?
active transport
3
What is the function of the xylem?
Transport water and mineral ions from roots to leaves
4
What is the function of phloem?
transport sucrose around the plant
5
Why do xylem cells have lignin in them?
To strengthen the cell
6
Are xylem cells living or dead?
Dead
7
Are phloem cells living or dead?
Dead
8
Which type of transport takes place in the xylem?
transpiration
9
Which type of transport takes place in the phloem?
translocation
10
What are stomata?
Pores/holes in the underside of the leaf
11
Why does a plant need stomata?
For gas exchange
12
Which cells control opening and closing of stomata?
Guard cells
13
How do guard cells control opening and closing of stomata?
When there is lots of water, water enters guard cells by osmosis and causes them to become plump and turgid. This opens the stomata. When there is less water, water leaves the guard cells by osmosis causing them to become thin and flaccid, closing the stomata
14
Does transpiration need energy?
No
15
Does translocation need energy
yes
16
How do phloem cells get energy for translocation?
Companion cells next to the phloem provide the energy.
17
What is transpiration?
movement of water from the roots of a plant up to the leaves where it evaporates through stomata.
18
Which factors can increase transpiration?
High temperature, low humidity, high air movement, high light intensity
19
Why does increasing temperature increase transpiration?
More water molecules evaporate from the leaf through the stomata. Rate of diffusion is increased
20
Why does decreasing humidity increase transpiration?
Makes a greater concentration gradient between the leaf and the air so diffusion is faster
21
Why does increasing air movement increase transpiration?
Maintains concentration gradient between leaf and air, increasing rate of diffusion
22
Why does increasing light intensity increase transpiration?
Rate of photosynthesis increases and stomata open for gas exchange, causing water to diffuse out.
23
Which piece of equipment can measure rate of transpiration?
potometer
24