ABA Oxford AQA

Where does ABA start in the plant?

• Shoot

• Root

• Guard Cells

• Leaf

In what conditions is ABA released? (Pick 2)

• Low Salinity

• High Salinity

• Low Water

• High Water

What cells control the opening of stomata?

(a)  

What process causes the guard cells to swell and open the stomata?

• Diffusion

• Osmosis

• Active Transport

• Facilitated diffusion

Is ABA Lipid Soluble?

• Yes

• No

To open the stomata, what is the first step that happens in the guard cells?

• K+ inwards channels in the guard cells open

• H+ ions are actively transported out of the guard cell

• Water rushes into the guard cells by osmosis

• A water potential inside the guard cell lowers.

To open the stomata, after H+ ions are actively transported out of the guard cell, what is the next step that happens in the guard cells?

• K+ inwards channels in the guard cells open

• H+ ions are actively transported out of the guard cell

• Water rushes into the guard cells by osmosis

• A water potential inside the guard cell lowers.

Why does water move into the guard cell when opening the stomata?

• There is a decrease in water potential due to the build up of K+ ions

• There is an increase in water potential due to the build up of K+ ions

• H+ ions have been actively transported out of the guard cell

How does ABA travel from the root to the guard cells?

• In the xylem

• In the pholem

• Through diffusion

Where does ABA act upon the guard cell?

• It diffuses into the guard cell and makes ROS

• It links to a receptor on the guard cell membrane

• It moves through a K+ channel

• It is actively transported into the guard cell