McGraw-Hill Online Learning Center Test

McGraw-Hill Online Learning Center Test


1. Review the image and answer the following questions.

Presence of what hormone(s) appears to trigger the onset of leaf abscission every autumn?

A. cytokinins
B. gibberellins
C. ethylene
D. abscisic acid


2. What is the purpose of leaf abscission?

A. to reduce the chance of the plant dying due to desiccation
B. to clear the way for the formation of new leaves
C. to prevent leaves from freezing
D. as an adaptation to deter predation
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