Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Plant Biology > Xylem > Flashcards

Xylem Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

What is lignin?

A

a complex polymer that binds with cellulose to provide great strength and rigidity to the cell walls of the xylem vessels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is capillary action?

A

To flow in opposition of gravitational forces (like a straw)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the adhesive property of water?

A

Attraction to charged or polar surfaces to stick together, allows for capillary action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the cohesive property of water?

A

Attraction of like molecules to stick together

water can create surface tension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is a hydrogen bond?

A

a intermolecular bond where the partial negative charge on the O of one molecule can form a hydrogen bond with the partial positive charge on the hydrogens of other molecules.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is transpiration?

A

the loss of water vapor from the stems and leaves of plants, aka a consequence of gas exchange in the leaf

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Does what flow through the xylem along or against the pressure gradient?

A

Along the pressure gradient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the pressure gradient of water via the xylem?

A

Low pressure in leaf
High pressure in roots

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is transpiration pull?

A

The tension force in a leaf cell wall caused by a negative pressure gradient within the leaf.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is abscisic acid (ABA)?

A

Plant hormone that can induce stress defense genes, closing of stomata, and to inhibit germination and early seedling growth.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What secretes abscisic acid?

A

Dehydrated mesophyll cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does abscisic acid trigger?

A

triggers the efflux of potassium from guard cells, decreasing water pressure within the cells (lose turgor)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are tracheids?

A

tapered cells that exchange water solely via pits, leading to a slower rate of water transfer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the two types of xylem vessels?

A

Annual vessels and spiral vessels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How does lignin deposit in annular vessels?

A

the lignin forms a pattern of circular rings at equal distances from each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How does lignin deposit in spiral vessels?

A

The lignin is present in the form of a helix or coil

17
Q

What increases thee surface area available for absorption in some root cells?

A

Root hairs

18
Q

What are the minerals that need to be taken up from the soil?

A

Mg, nitrates, Na, K, PO

19
Q

For what do the roots take up magnesium?

A

Chlorophyll

20
Q

For what do the roots take up nitrates?

A

Amino acids

21
Q

Where are H+ ions stored in root cells?

A

The vacuole

22
Q

What do the protein pumps of root cells actively expel?

A

H+ ions

23
Q

What is the symplastic pathway?

A

water moves continuously through the cytoplasm of cells (connected via plasmodesmata)

24
Q

What is the apoplastic pathway?

A

water cannot cross the Casparian strip and is transferred to the cytoplasm of the endodermis

25
Q

What are halophytes?

A

plants that have adaptations to survive in environments of high salinity

26
Q

What are xerophytes?

A

plants that have adaptations to survive in dry conditions

27
Q

What adaptions do halophytes use to tolerate salty conditions?

A

Cellular sequestration
Tissue partitioning
Root level exclusion
Salt excretion
Altered flowering schedule

28
Q

What is cellular sequestration?

A

halophytes can sequester toxic ions and salts within the cell wall or vacuoles

29
Q

What is tissue partitioning?

A

plants may concentrate salts in particular leaves, which then drop off (abscission)

30
Q

What is root level exclusion?

A

plant roots may be structured to exclude ~95% of the salt in soil solutions

31
Q

What is salt excretion?

A

certain parts of the plant (e.g. stem) may contain salt glands which actively eliminate salt

32
Q

What is altered flowering schedule?

A

halophytes may flower at specific times (e.g. rainy seasons) to minimise salt exposure

33
Q

What are some adaptations that allow xerophytes to tolerate dry conditions?

A

Reduced leaves
Rolled leaves
Thick, waxy cuticle
Stomata in pits
Low growth
CAM physiology

34
Q

What is the reason behind reducing leaves?

A

reducing the total number and size of leaves will reduce the surface area available for water loss

35
Q

What is the reason behind rolling leaves?

A

rolling up leaves reduces the exposure of stomata to the air and hence reduces evaporative water loss

36
Q

What is the reason for having a thick, waxy cuticle?

A

having leaves covered by a thickened cuticle prevents water loss from the leaf surface

37
Q

What is the reason for having stomata in pits?

A

having stomata in pits, surrounded by hairs, traps water vapour and hence reduces transpiration

38
Q

What is the reason behind low growth plants?

A

low growing plants are less exposed to wind and more likely to be shaded, reducing water loss

39
Q

What is the reason for CAM physiology?

A

plants with CAM physiology open their stomata at night, reducing water loss via evaporation

Plant Biology (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions