Polar bears are classified as a threatened species because

a. they have reduced hunting success.
b. they have reduced reproductive success.
c. their habitat is decreasing in size.
d. all of these


D

Biology & Microbiology

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The diagram below shows inbreeding between _________ which, over time, could lower the fitness of the population. This lowering of fitness because of inbreeding is called _________.



A. siblings; inbreeding depression
B. cousins; inbreeding depression
C. siblings; genetic drift
D. cousins; genetic drift
E. siblings; sexual selection

Biology & Microbiology

During inspiration (a.k.a. inhalation) of air into the lung of a mammal

A. the intercostal muscles relax. B. the chest cavity has a positive pressure. C. the diaphragm contracts. D. the diaphragm moves upward. E. the rib cage moves down.

Biology & Microbiology

The _______ nerve carries signals from the retina to the visual cortex of the cerebrum.

Fill in the blank(s) with correct word

Biology & Microbiology

Explain how dissolved sugar is transported in the phloem by means of a pressure gradient. What will be an ideal response?

Biology & Microbiology