The Following Questions Refer to the Evolutionary Tree in Figure

question 19

Multiple Choice

The following questions refer to the evolutionary tree in Figure 22.2.
The tree's horizontal axis is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.


-How many separate species, both extant and extinct, are depicted in this tree?

• A)2
• B)3
• C)4
• D)5

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Definitions:

Acute Infectious Disease

A rapidly developing infection caused by bacteria, viruses, fungi, or parasites, characterized by symptoms that are severe but often brief in duration.

False Membrane

A thick layer of fibrous tissue that forms over a mucous membrane surface as a result of inflammation or injury.

Gauge

The size of a needle bore; the smaller the number, the larger the needle bore.

Needle Bore

The internal diameter of a needle, affecting the flow rate of injected or withdrawn fluids.