Cell Membranes Allow Certain Molecules to Pass, While Blocking Others

question 93

Multiple Choice

Cell membranes allow certain molecules to pass, while blocking others. This property is called

• A) impermeable.
• B) freely permeable.
• C) selectively permeable.
• D) actively permeable.
• E) none of the above

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Definitions:

Direct Motor Pathways

Neural paths descending from the brain to the spinal cord responsible for the voluntary movement of muscles.

Sensory Adaptation

The process by which sensory receptors become less sensitive to constant stimuli over time, allowing organisms to focus on changes in their environment.

Primary Receptors

Sensory structures that respond to environmental stimuli by initiating a sensory signal.

Free Nerve Endings

Sensory receptors located near the surface of the skin that can detect pain, temperature, and touch.