Filters
Question type

Study Flashcards

Removing the top of a plant to create fuller growth involves which of the following hormones?


A) auxins
B) ethylene
C) gibberellins
D) cytokinins

E) A) and D)
F) A) and B)

Correct Answer

verifed

verified

Which plant hormone produced in apical meristems inhibits the growth of axillary buds?


A) abscisic acid
B) auxin
C) cytokinin
D) ethylene
E) gibberellin

F) A) and E)
G) C) and D)

Correct Answer

verifed

verified

________ is often referred to as the "stress" hormone since it initiates and maintains seed and bud dormancy.


A) Ethylene
B) Cytokinins
C) Abscisic acid
D) Gibberellins

E) B) and C)
F) None of the above

Correct Answer

verifed

verified

Which of the following pertain to movement of plants?


A) nastic movements
B) thigmotropism
C) phototropism
D) gravitropism
E) All of the choices are correct.

F) None of the above
G) A) and B)

Correct Answer

verifed

verified

How does gibberellin actually work?


A) In the presence of blue light,it triggers additional photosynthesis and growth.
B) It attaches to a plasma membrane receptor and results in gene activation to produce the enzyme amylase that releases sugars for additional cell growth,division,and elongation.
C) In the presence of light,it increases the formation of additional DNA that codes for additional plant structures.
D) In the presence of unidirectional light,it moves to the shady side and activates an ATP-driven proton pump that results in weakened cell walls and eventual elongation.
E) In the presence of light,it increases the turgor pressure of the cell and accelerates growth.

F) A) and D)
G) B) and D)

Correct Answer

verifed

verified

Explain how a hormone will trigger the signal transduction pathway in a plant.

Correct Answer

verifed

verified

1.Receptor: a molecule in the plasma mem...

View Answer

Plants could readily develop seasonal responses for flowering based on temperature changes but have "elected" through evolution to manage their rhythms based on a comparison of daylight and darkness.Why has the day-night ratio system been selected?


A) Temperature has no effect upon plant biochemistry.
B) Temperature is a gradation but day/night is all-or-nothing.
C) A plant's nervous system is tuned to light stimuli and not to temperature stimuli.
D) Temperatures fluctuate widely across seasons and from year to year,but photoperiod comparisons are a more reliable indicator of season.

E) All of the above
F) C) and D)

Correct Answer

verifed

verified

Explain the mechanisms required for a Venus flytrap to close its trap when stimulated by an insect.

Correct Answer

verifed

verified

Turgor pressure is required to cause the Venus flytrap to close.Turgor pressure is created when the trigger cells are stimulated.An electrical charge is transmitted throughout the lobes of the leaf.One explanation for the cause of this electrical charge is that the lobes of the leaf secrete hydrogen ions into the cell walls allowing them to swell by osmosis.Another explanation is that the lobes on the inner portion of the midrib lose ions leading to a water loss through osmosis and collapsing the cells.

Which statement is NOT true about photoperiodism?


A) A short-day plant flowers when the day length is shorter than a critical length.
B) A day-neutral plant flowers according to some form of regulation other than photoperiodism.
C) A long-day plant will flower when the day length is longer than a critical length.
D) The phytochrome form Pfr is converted to Pr in daylight,producing the active form that induces flowering in long-day plants.

E) C) and D)
F) B) and D)

Correct Answer

verifed

verified

  The cylinders in this experiment represent a 24-hour period. The light area represents light periods during a 24-hr. period and the dark area represents dark periods during a 24-hr. period. The critical length of dark vs. light periods for flowering is depicted by the dotted line. Note that some plants are flowering and some are not flowering. Study the results of this experiment on photoperiodism and flowering to determine whether the following statements are true or false. -A hormone is produced in small amounts in a tissue,and it causes a physiological action within that same tissue soon after its production. The cylinders in this experiment represent a 24-hour period. The light area represents light periods during a 24-hr. period and the dark area represents dark periods during a 24-hr. period. The critical length of dark vs. light periods for flowering is depicted by the dotted line. Note that some plants are flowering and some are not flowering. Study the results of this experiment on photoperiodism and flowering to determine whether the following statements are true or false. -A hormone is produced in small amounts in a tissue,and it causes a physiological action within that same tissue soon after its production.

A) True
B) False

Correct Answer

verifed

verified

Which of the following plant hormones was studied in the 1880s by Charles and Francis Darwin in experiments on phototropism?


A) abscisic acid
B) auxin
C) cytokinin
D) ethylene
E) gibberellin

F) B) and C)
G) D) and E)

Correct Answer

verifed

verified

Which of the following is a receptor that responds to light?


A) phytochrome
B) phototropin
C) gibberellins
D) cytokinins
E) Phytochrome and phototropin are correct.

F) None of the above
G) A) and B)

Correct Answer

verifed

verified

A plant's response to an external stimulus involves receptors.A receptor that responds to light normally contains


A) a series of relay proteins.
B) a pigment component.
C) a transduction pathway.
D) an end product of a metabolic pathway.

E) B) and D)
F) B) and C)

Correct Answer

verifed

verified

Which of the following plant hormones prevents plant tissues from senescing,or aging?


A) abscisic acid
B) auxin
C) cytokinin
D) ethylene
E) gibberellin

F) C) and E)
G) A) and B)

Correct Answer

verifed

verified

Which of the following plant hormones stimulates the ripening of fruit and inhibits plant growth?


A) abscisic acid
B) auxin
C) cytokinin
D) ethylene
E) gibberellin

F) A) and C)
G) A) and D)

Correct Answer

verifed

verified

Which of the following plant hormones was discovered in infected rice seedlings that grew extremely tall and slender with "foolish seedling disease"?


A) abscisic acid
B) auxin
C) cytokinin
D) ethylene
E) gibberellins

F) B) and D)
G) A) and B)

Correct Answer

verifed

verified

E

Which of the following is NOT a physiological change related to photoperiodism?


A) seed germination
B) root branching
C) breaking bud dormancy
D) some flowering
E) onset of senescence

F) B) and E)
G) C) and D)

Correct Answer

verifed

verified

  The cylinders in this experiment represent a 24-hour period. The light area represents light periods during a 24-hr. period and the dark area represents dark periods during a 24-hr. period. The critical length of dark vs. light periods for flowering is depicted by the dotted line. Note that some plants are flowering and some are not flowering. Study the results of this experiment on photoperiodism and flowering to determine whether the following statements are true or false. -If a plant is placed on its side,cells on the lower side of the stem will respond to gravity and elongate,making the stem turn so that it continues to grow downward. The cylinders in this experiment represent a 24-hour period. The light area represents light periods during a 24-hr. period and the dark area represents dark periods during a 24-hr. period. The critical length of dark vs. light periods for flowering is depicted by the dotted line. Note that some plants are flowering and some are not flowering. Study the results of this experiment on photoperiodism and flowering to determine whether the following statements are true or false. -If a plant is placed on its side,cells on the lower side of the stem will respond to gravity and elongate,making the stem turn so that it continues to grow downward.

A) True
B) False

Correct Answer

verifed

verified

False

Which of the following statements best describes how plants use hormones during signal transduction?


A) The hormone will bind to a specific receptor in the plasma membrane.It will then trigger a series of relay proteins that alter the signal into one that will impact the cellular machinery.Once the machinery is altered a change in gene expression will occur causing a change in the physical expression of the plant.
B) The hormone will trigger a series of relay proteins to alter the signal into one that will impact the cellular machinery.Once the signal is changed the hormone will bind to a specific receptor in the plasma membrane.It will then cause a change in gene expression to occur causing a change in the physical expression of the plant.
C) The hormone will bind to a specific receptor in the plasma membrane.It will then trigger a series of relay proteins that alter the signal into one that will impact the cellular machinery.Once the machinery is altered a change in the physical expression will occur causing a change in the actual genes of the plant.
D) None of these describes how plants use hormones during signal transduction.

E) A) and C)
F) A) and B)

Correct Answer

verifed

verified

Which of the following plant hormones breaks dormancy in seeds and buds when applied to the plant?


A) abscisic acid
B) auxin
C) cytokinin
D) ethylene
E) gibberellins

F) B) and D)
G) C) and E)

Correct Answer

verifed

verified

Showing 1 - 20 of 52

Related Exams

Show Answer