Many trees shed their leaves during the autumn months when conditions are not suitable for photosynthesis. Which characteristic
of living things is BEST represented when a tree sheds it leaves during the autumn? A)metabolism B)reproduction C)use of a genetic code D)response to external stimuli
The correct answer is option D) "response to external stimuli".
Explanation:
The phenomenon of tree shedding their leaves during the autumn months is an example of plants response to external stimuli. The deciduous trees start shedding their leaves when light levels and temperatures drop, as a result of the flow of auxin being reduced and the levels of the hormone ethylene rise in the leaves. This process allows the trees to survive winter by conserving resources and protecting from being blown by the winds.
Answer: The vulnerable embryo must be sheltered from desiccation and other environmental hazards. In both seedless and seed plants, the female gametophyte provides protection and nutrients to the embryo as it develops into the new generation of sporophyte.
