The Loss of Mayflies from a Stream Suggests That the Quality

question 82

Multiple Choice

The loss of mayflies from a stream suggests that the quality of water is declining; therefore, mayflies are a(n) ____ species.​

• A) ​degraded
• B) ​endangered
• C) ​threatened
• D) ​keystone
• E) indicator​

Analyze the concepts of consciousness and altered states.

Comprehend the psychological theories behind dreams and their interpretation.

Understand the effects and dangers of drug use and dependence.

Identify the role of key hormones and brain structures in sleep and consciousness.

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Definitions:

Medullary Concentration Gradient

A gradient of solute concentration in the kidney medulla that facilitates water reabsorption and urine concentration through osmosis.

Urea Molecules

Organic compounds and the main nitrogen-containing substance in the urine of mammals, formed in the liver from ammonia and carbon dioxide.

Ascending Limb

The part of the loop of Henle in the nephron that transports fluid from the lower to the upper parts of the kidney.

Filtrate Reabsorption

The process by which the kidneys recover water and essential ions from the filtrate during urine formation.