If the Pacemaker Cells in the SA Node Become More

question 91

Multiple Choice

If the pacemaker cells in the SA node become more permeable to potassium ions, the

• A) heart rate will increase.
• B) heart rate will decrease.
• C) membrane will depolarize.
• D) membrane will hyperpolarize.
• E) both B and D

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Definitions:

Just-noticeable Difference

The minimum difference in stimulus intensity required to detect a difference between two stimuli.

Thalamus

A part of the brain that serves as a central relay station for sensory information, excluding smell.

Cortex

The outer layer of the brain involved in higher-order brain functions such as thought, language, and decision making.

Pons

A part of the brain located in the brainstem that plays key roles in regulating sleep, breathing, and coordination between different parts of the brain.