Brainscape's Knowledge GenomeTM

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


See full index

Bio 167 > Chapter 39 > Flashcards

Chapter 39 Flashcards

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

Carolus Linnaeus noted that flowers of different species opened at different times of day and could be used as a _________ or floral clock

A

horologium florae,

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

A potato left growing in darkness produces shoots that look unhealthy, and it lacks elongated roots
These are morphological adaptations for growing in darkness, collectively called ___________

A

etiolation

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

After exposure to light, a potato undergoes changes called __________, in which shoots and roots grow normally

A

de-etiolation (“Greening”)

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

A potato’s response to light is an example of __________

A

cell-signal processing

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

Internal and external signals are detected by ________, proteins that change in response to specific stimuli

A

receptors

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

In de-etiolation, the receptor is a _________ capable of detecting light

A

phytochrome

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

______________ transfer and amplify signals from receptors to proteins that cause responses

A

Second messengers

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

Two types of second messengers play an important role in de-etiolation: ___________ _______________

A

Ca2+ ions and cyclic GMP (cGMP)

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

The phytochrome receptor responds to light by ….

A

Opening Ca2+ channels, which increases Ca2+ levels in the cytosol
Activating an enzyme that produces cyclic GMP

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

De-etiolation activates enzymes that

A
  • Function in photosynthesis directly
  • Supply the chemical precursors for chlorophyll production
  • Affect the levels of plant hormones that regulate growth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Plant hormones are …

A

chemical signals that modify or control one or more specific physiological processes within a plant

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

Any response resulting in curvature of organs toward or away from a stimulus is called a _________

A

tropism

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

In the late 1800s, Charles Darwin and his son Francis conducted experiments on __________, a plant’s response to light. They observed that a grass seedling could bend toward light only if the tip of the _______ was present. They postulated that a signal was transmitted from the tip to the __________.

A

phototropism: coleoptile : elongating region

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

In 1913, Peter Boysen-Jensen demonstrated that the signal was a ____________

A

mobile chemical substance

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

Plant hormones are produced in very low concentration, but a minute amount can greatly affect ____________ of a plant organ

A

growth and development

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

In general, hormones control plant growth and development by affecting the _______, ________, and __________ of cells

A

division, elongation, and differentiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

The term auxin refers to any chemical that promotes _____________

A

elongation of coleoptiles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

_____________ is a common auxin in plants; in this lecture the term auxin refers specifically to IAA

A

Indoleacetic acid (IAA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Auxin is produced in ________ and is transported down the stem

A

shoot tips

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Auxin transporter proteins move the hormone from the _______________________________

A

basal end of one cell into the apical end of the neighboring cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Cytokinins are so named because they ________________

A

stimulate cytokinesis (cell division)

22
Q

_________ are produced in actively growing tissues such as roots, embryos, and fruits

A

Cytokinins

23
Q

___________ work together with auxin to control cell division and differentiation

A

Cytokinins

24
Q

Cytokinins, auxin, and strigolactone interact in the control of _____________, a terminal bud’s ability to suppress development of axillary buds
If the terminal bud is removed, plants become bushier

A

apical dominance

25
Q

Cytokinins slow the aging of some plant organs by inhibiting _____, ______ and_____, and mobilizing nutrients from surrounding tissues

A

protein breakdown, stimulating RNA and protein synthesis,

26
Q

_________ have a variety of effects, such as stem elongation, fruit growth, and seed germination

A

Gibberellins

27
Q

The major sites of giberellin production are young roots and leaves. Giberellins are best known for stimulating stem and leaf growth by ____________ and _____________.

A

enhancing cell elongation and cell division

28
Q

In many plants, both____________ must be present for fruit to develop
____________ are used in spraying of Thompson seedless grapes

A

auxin and gibberellins: Gibberellins

29
Q

After water is imbibed, release of gibberellins from the embryo signals seeds to ___________

A

germinate

30
Q

__________ are chemically similar to the sex hormones of animals. They induce cell elongation and division in stem segments. They slow leaf abscission (leaf drops) and promote xylem differentiation.

A

Brassinosteroids

31
Q

_________ slows growth

Two of the many effects of _______ Seed dormancy and Drought tolerance

A

Abscisic acid (ABA)

32
Q

Seed________ ensures that the seed will germinate only in optimal conditions

A

dormancy

33
Q

In some seeds, dormancy is broken when ABA is removed by ______________

A

heavy rain, light, or prolonged cold

34
Q

___________ germination can be caused by inactive or low levels of ABA

A

Precocious (early)

35
Q

_______ is the primary internal signal that enables plants to withstand drought

A

ABA

36
Q

ABA accumulation causes ________to close rapidly

A

stomata

37
Q

The hormones called ___________
Stimulate seed germination
Help establish mycorrhizal associations
Help control apical dominance

A

strigolactones

38
Q

Strigolactones are named for _______ plants

A

parasitic Striga

39
Q

Striga seeds germinate when host plants exude _________through their roots

A

strigolactones

40
Q

Plants produce ________ in response to stresses such as drought, flooding, mechanical pressure, injury, and infection. The effects of _________ include response to mechanical stress, senescence, leaf abscission, and fruit ripening

A

ethylene

41
Q

Ethylene induces the ___________, which allows a growing shoot to avoid obstacles. The ___________ consists of a slowing of stem elongation, a thickening of the stem, and horizontal growth

A

triple response

42
Q

________ mutants fail to undergo the triple response after exposure to ethylene

A

Ethylene-insensitive

43
Q

________ is the programmed death of cells or organs

A

Senescence

44
Q

A burst of ethylene is associated with __________, the programmed destruction of cells, organs, or whole plants

A

apoptosis

45
Q

A change in the balance of auxin and ethylene controls leaf _________, the process that occurs in autumn when a leaf falls

A

abscission

46
Q

A burst of ethylene production in a fruit triggers the ________ process which triggers more ethylene. Fruit producers can control _______ by picking green fruit and controlling ethylene levels

A

ripening

47
Q

Light cues many key events in plant growth and development> Effects of light on plant morphology are called __________

A

photomorphogenesis

48
Q

A graph called an__________ depicts relative response of a process to different wavelengths: useful in studying any process that depends on light

A

action spectrum

49
Q

Different plant responses can be mediated by the same or different photoreceptors. There are two major classes of light receptors: _________ and ______________

A

blue-light photoreceptors and phytochromes

50
Q

Various _________ photoreceptors control hypocotyl elongation, stomatal opening, and phototropism

A

blue-light

51
Q

__________ are pigments that regulate many of a plant’s responses to light throughout its life
These responses include seed germination and shade avoidance

A

Phytochromes

Bio 167 (13 decks)

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