Transport in Plants

Question 1

Diffusion works in liquids, _________, and __________.

Answer 1

gels

gasses

Question 2

Diffusion:

Soluble chemicals diffuse from a ________ to ________.

Answer 2

high

low

Question 3

Is there a particular enzyme needed for diffusion to work?

Answer 3

yes, aquaporins

Question 4

The energy for diffusion comes from ___________.

Answer 4

ATP

Question 5

The rate of diffusion can be sped up by _________ the solution, or making a __________ concentration.

Answer 5

heating

gradient

Question 6

Osmosis refers to the movement of __________ across membranes.

Answer 6

water

Question 7

Osmosis:

A red blood animal cell placed into a hypotonic solution would ___________.

Answer 7

burst/lysed

Question 8

Osmosis:

A plant cell placed into a hypotonic solution would _________.

Answer 8

be turgid

Question 9

Osmosis:

You could make a cell shrivel by placing it into a(n) ___________ solution.

Answer 9

hypertonic

Question 10

Osmosis:

Your blood and cells live in a(n) ___________ solution.

Answer 10

isotonic

Question 11

Moving molecules across membranes:

Which substances/chemicals can freely pass across cell membranes?

Answer 11

H+

Question 12

What can pass freely across most membranes via aquaporins?

Answer 12

water

Question 13

Sugars, amino acids, etc., cross membranes via _______________.

Answer 13

channels

Question 14

In facilitated diffusion, substances (like glucose) move into cells if the concentration inside the cell is ___________ than outside the cell.

Answer 14

lower

Question 15

In facilitated diffusion:

substances move from _________ to ________.

Answer 15

high

low

Question 16

In facilitated diffusion:

Is any extra energy needed for it to work?

Answer 16

no

Question 17

In facilitated diffusion:

What is the “facilitator”?

Answer 17

channel

Question 18

In facilitated diffusion:

Why is it described as passive transport?

Answer 18

No extra energy is needed

Question 19

In Active Transport:

Substances move from ________ to ________

Answer 19

low

high

Question 20

In active transport:

Is any extra energy needed for it to work?

Answer 20

yes, ATP

Question 21

In active transport:

Why is it described as “active” transport?

Answer 21

Energy is needed

Question 22

Water potential equation:

Ψ total =

Answer 22

Ψ solute + Ψ pressure

Question 23

Distilled water has Ψs of ___________.

Answer 23

0

Question 24

Water moves to a Ψ total that is __________.

Answer 24

more negative

Question 25

The most negative Ψ total is found in the __________.

Answer 25

solution

Question 26

In tension, the __________ is negative.

Answer 26

Ψp of leaf

Question 27

Water potential equation: Generally, the _________ (plant vascular tissue) is under tension and the _________ (plant vascular tissue) has a positive pressure.

Answer 27

phloem xylem

Question 28

Positive pressure creates _________ flow.

Answer 28

unidirectional

Question 29

Root pressure: Endodermis has a waxy layer, the __________, that has 2 functions.

Answer 29

casparian strip

Question 30

Endodermis functions: Screens out _________ from entering the rest of the plant.

Answer 30

toxins

Question 31

Endodermis functions: Prevents _________ moving apoplastically out of the stele (vascular cylinder).

Answer 31

water

Question 32

In the root, the ________ layer helps maintain a higher mineral/ion concentration inside the stele (vascular cylinder) using active/passive transport.

Answer 32

endodermis

Question 33

This gradient creates a Ψ total (positive/0/negative) inside the stele (vascular cylinder) relative to the cortex and soil.

Answer 33

negative

Question 34

In young shoots, when root pressure exceeds tension _________ occurs (visible on damp mornings- e.g. strawberry leaf photo in lecture).

Answer 34

guttation

Question 35

Leaves Water evaporation causes an increase in ___________ in the mesophyll. This pushes/pulls on the water column via the ___________ property of water, creating ____________ and a Ψ p that is positive/negative.

Answer 35

tension pulls H-bond cohesion negative

Question 36

Leaves: Water sticks to the cellulose cell walls holding it up against gravity due to __________.

Answer 36

adhesion

Question 37

The stoma is the _________ surrounded by 2 _________ cells.

Answer 37

opening guard

Question 38

Stomata open when ________ions move into the guard cell tonoplast. This makes their Ψ total =_______ relative to the subsidiary cells and water moves in/out the guard cell.

Answer 38

K+ positive out

Question 39

Stomata are signaled to close by the drought stress hormone ___________.

Answer 39

ABA

Question 40

Stomata close when ________ ions move in/out the guard cell tonoplast. This makes their Ψ total= ________ relative to the subsidiary cells and water moves out of the guard cell.

Answer 40

K+ out negative

Question 41

Sugar in phloem moves from _________ to ________.

Answer 41

source sink

Question 42

Sugar is loaded into phloem in a _________ and moves to and is unloaded in a __________.

Answer 42

source sink

Question 43

Phloem: Examples of sources are ___________ Examples of sinks are ____________

Answer 43

leaves, stem roots, young shoot, flowers, fruit

Question 44

Sugar is loaded in phloem by ________transport using __________ and ___________.

Answer 44

active transport osmosis bulk flow

Question 45

This creates a Ψ s that is very positive/negative.

Answer 45

negative

Question 46

The source phloem Ψ total is so _________ that it pulls water from the adjacent __________.

Answer 46

positive vessel (xylem)

Question 47

Water moving into the sieve cell creates a Ψp =very positive/negative

Answer 47

negative

Question 48

At a sink, sugar is pulled out and the Ψ total is now more positive/negative relative to the nearby xylem and the water moves in/out.

Answer 48

positive out