Theme 4 Homeostasis In Land Plants Part 3

Question 1

In which ways do plants move water and solutes

Answer 1

Into and out of cells

Laterally from cell to cell

Over long distances from the root to shoot or vise versa

They move substances across cell membranes by both active and passive transport

Question 2

What is the short distance transport in plants

Answer 2

Moving solutes

into and between cells from root hairs

To and from vascular tissues (xylem and phloem)

Question 3

What is the long distance transport in plants

Answer 3

Moving solutes between the root and the shoot part of the plant

Up and down the whole plant

Question 4

What does the xylem transport

The pholem

Answer 4

H2O and o2

Sugars

Question 5

What is osmosis

Answer 5

How the water moves

Passive movement of water across a selectively permeable membrane

Question 6

What are aquaporin proteins

Answer 6

Proteins that let water move rapidly through hydrophobic membrane core

For large amounts of water transport

Question 7

What minerals can easily diffuse easily into a cell

Answer 7

H2O co2 o2

Question 8

What is water potential

Answer 8

The potential energy of water

The driving force that determines which way the water moves

Question 9

What is the potential energy of pure water

Answer 9

0 mega pascals, no solutes, standard atmospheric pressure

Question 10

What makes up water potential

Answer 10

Solute potential + pressure potential

Question 11

Which way does water move

Answer 11

From high water potential to low water potential

Question 12

What lowers water potential

Answer 12

The presence of solutes

In solute added to pure water (0 megapascals). The water potential turns negative

Adding solution will never make postive impact, solute potential always negative

Question 13

What is pressure potential

When does it increase water potential

Answer 13

The force required to stop water movement

Can be postive pressure or negative pressure

If you apply postive pressure the water potential goes up

If you apply negative pressure the water potential goes down

Question 14

If you add solute to water on one side…

Answer 14

The water potential on that side goes down

Water moves to that side by osmosis (move to lower potential)

Question 15

If you add same amount of pressure potential and solute potential…

Answer 15

Pushing down into water makes positive potential

Solutes make negative potential

Cancels

Net zero change in water potential, no net movement on both sides it’s zero

Question 16

If adding more pressure potential than solute potential to one side…

Answer 16

Net Increase in water potential of the solution on that side

So water moves to the left (to lower potential

Question 17

If apply more negative pressure (pulling water up instead of pushing) to one side and have less solute on the other side ….

Answer 17

Side with negative pressure has less water potential than side with solute

So water moves to side of negative pressure

(Left)

Moves until equilibrium is reached on both sides

Question 18

Which situation applies to the plants

Answer 18

The negative pressure one one side and solutes on other

Transpiration out of stomatal pores acts as a vaccume

The lignin in xylem makes it so the vaccume doesn’t collapse the xylem.

Then solutes and water are pushed up

Question 19

Pic not in notes

Answer 19

Ok

Question 20

Plants always try to maintain …

Answer 20

High solute concentration inside of the cell

Means in the plants cell the water potential is negative. (Cause of solutes potential)

Always drawing more water in

Question 21

How do plants counter the negative cell water potential to reach equilibrium

Answer 21

The massive central vacuole takes water into itself and maintains turgor pressure

Question 22

What is the tonoplast membrane what does it do

Answer 22

The membrane of the central vacuole

Helps maintain turgor oressure

Question 23

What is plasmolysis

Answer 23

The wilting in plants that happens because the soil is dry (water potential in soil is low)

Water travels to soil from plants

Plant losing water wilts

Question 24

Water will always follow….

What does the plant do

Answer 24

The solutes

If taking more solutes, more water following

The pressure potential goes up (more postive turgor pressure)

The plant adjusts the solutes to keep itself turgid and let water come in until equilibrium is reached

Question 25

Water goes through the main xylem to what cells

Answer 25

The mesophyll cells

Question 26

Water moving into the cell increases

Answer 26

Pressure potential

This is how equilibrium is reached

Question 27

Water potential calcs

Answer 27

Ok

Question 28

If flaccid cell is placed in pure water what happens

Answer 28

Pure water is 0mpa

The water potential outside is higher than the inside

Water potential on inside of cell is lower (negative)

So water moves into the cell making it turgid

Question 29

What happens if a flaccid cell is placed in a sucrose solution

Answer 29

There’s no water anywhere outside

The water potential in the solution is lower than the potential in the cell

So water moves out of the cell and into the sucrose solution

The cell becomes plasmolyzed

Question 30

Question from slides

Answer 30

Takes in more solutes to become more turgid

Water follows the solutes

Question 31

What are the 3 pathways that water and solutes move up the xylem

Answer 31

The apoplastic and the symplastic

Cell to cell movement

Question 32

What is the apoplastic pathway

Answer 32

Water moves to the endodermis until it reaches the casparian stripe at endodermis . When it reaches the stripe is gets screened

Never gets into the cell, never crosses the plasma membrane

Moves through spaces in cell membrane (intercellular spaces)

Question 33

What is the symplastic pathway

Answer 33

Water flows across into and through the plasma membrane

Inside the cell, cytoplasm

Connected by plasmodesmata which take water to the inside of other cell

Question 34

What’s good about the symplastic route

Answer 34

Water can go directly to xylem once it has entered the inside of the cell

Question 35

What route is fastest

Answer 35

The apoplastic route

Goes straight to endodermis

Question 36

What is cell to cell transport

Answer 36

Moves through or between

A combo

Question 37

What’s past the endoderm

Answer 37

The xylem

Question 38

What type of transport is apoplastic

What about symplastic

Answer 38

Passive (not crossing membrane)

Could be passive or active depending on concentration gradient