Biology Test Plant Biology 5

Question 1

Which plant hormone promotes cell elongation and is produced primarily in shoot apical meristems?

Accepted Answer

Auxin (IAA)

Answer

Auxin (indole-3-acetic acid) is produced in shoot tips and promotes cell elongation by loosening cell walls, driving phototropic and gravitropic responses.

Question 2

What is the significance of alternation of generations in plant life cycles?

Accepted Answer

Plants alternate between a diploid sporophyte and a haploid gametophyte generation

Answer

Alternation of generations refers to the alternating multicellular diploid sporophyte (2n) and haploid gametophyte (n) phases in the plant life cycle.

Question 3

Which of the following best describes apical dominance in plants?

Accepted Answer

The apical bud suppresses the growth of lateral buds

Answer

Apical dominance occurs when the apical meristem produces auxin that inhibits the growth of lateral (axillary) buds below it.

Question 4

What is the difference between C3 and CAM plants in terms of carbon fixation timing?

Accepted Answer

C3 plants fix carbon during the day; CAM plants fix carbon at night

Answer

C3 plants fix CO2 into a 3-carbon compound during daylight hours, while CAM plants open stomata at night to fix CO2 into organic acids, releasing it during the day.

Question 5

What term describes the curling movement of a tendril around a support structure in climbing plants?

Accepted Answer

Thigmotropism

Answer

Thigmotropism is a plant's directional growth response to physical touch or contact, allowing tendrils to coil around supports.

Biology Practice Test

Biology Practice Test

Biology Test Plant Biology 5