The First Phase of the Refractory Period Is Called the Absolute

question 54

Multiple Choice

The first phase of the refractory period is called the absolute refractory period. What happens during this phase?

• A) K⁺ channels open.
• B) K⁺ channels close.
• C) Na⁺ channels open.
• D) Na⁺ channels close.

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Definitions:

Reservoir Host

An organism that harbors a pathogen for an extended period, without being affected by it, serving as a source of infection for other species.

Pathogen

A biological agent that causes disease or illness to its host.

Carrier

An individual or entity that transports goods or people; in genetics, it also refers to someone who has one copy of a recessive gene for a disease.

Unpasteurized Milk

Milk that has not undergone pasteurization, a process to kill harmful bacteria by heating the milk for a short time.