In the Figure Shown, the Willow Tree Population Leveled Off

question 20

Multiple Choice

In the figure shown, the willow tree population leveled off at 475 trees and remained stable in the early 1980s. This most likely occurred because the

• A)trees occupied all of the available space that willows were able to occupy.
• B)tree seedlings were shaded by the grasses shown in the illustration.
• C)population growth rate exceeded the death rate.
• D)trees depleted all of the nutrients in the soil and the trees could no longer grow.

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Definitions:

ADH

Antidiuretic hormone, also known as vasopressin, which helps regulate water balance in the body by controlling the amount of water reabsorbed by the kidneys.

Alcohol

An organic compound characterized by one or more hydroxyl (-OH) groups attached to a carbon atom.

Urine Production

The process by which the kidneys filter the blood, removing waste products and excess substances to form urine.

Angiotensinogen

A glycoprotein produced by the liver that is the precursor to angiotensin, playing a key role in blood pressure regulation.