If the Pacemaker Cells in the SA Node Become More

question 173

Multiple Choice

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

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

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Definitions:

Element

A pure chemical substance consisting of one type of atom, distinguished by its atomic number.

Electrolytes

Minerals in the body that have an electric charge, such as sodium, potassium, calcium, and magnesium, and are vital for numerous bodily functions including fluid balance and nerve transmission.

Water

Water is a transparent, tasteless, odorless, and nearly colorless chemical substance that is the main constituent of Earth's streams, lakes, and oceans, and the fluids of most living organisms.

Ions

Ions are atoms or molecules with a net electric charge due to the loss or gain of one or more electrons.