Bio Chapter 39 – Flashcards
Unlock all answers in this set
Unlock answersquestion
How do plant and animal hormones differ?
answer
In plants more so than in animals, it is the balance between existing hormones, rather than hormones acting in isolation, that controls growth and development.
question
Evergreen trees lose their leaves _____.
answer
steadily all year
question
The breakdown of chlorophyll reveals the _____ pigments of a leaf.
answer
carotenoid
question
The formation of the abscission layer cuts off transport of substances to and from the leaf. As the concentration of sugar trapped within a leaf increases, _____ pigments are produced.
answer
anthrocyanin
question
The protective layer that forms between the abscission layer and the stem consists of _____.
answer
densely colored cells filled with a waxy layer
question
After leaf abscission, growth will resume from the _____.
answer
axillary bud
question
_____ trees lose their leaves in preparation for winter.
answer
deciduous
question
What is the physical basis of the phototropic response?
answer
cell elongation
question
Where does the majority of stem growth in a plant occur?
answer
apical meristem
question
true or false? Hormones can function at very low concentrations.
answer
true
question
Auxin transport is _____; it always travels _____.
answer
polar; downward
question
How does auxin produce gravitropism in a plant that is placed on its side?
answer
Auxin accumulates on the lower surface of the root and inhibits elongation of cells in that region.
question
How does auxin produce phototropism?
answer
Auxin accumulates in cells on the side of the plant opposite the source of light and stimulates their elongation.
