In an ECG, Researchers Detect Heart Rate by Measuring

question 23

Multiple Choice

In an ECG, researchers detect heart rate by measuring:

• A) the sound of the heart beating.
• B) the electrical activity generated by heart muscle in the process of contracting.
• C) the change in pressure in the chest cavity, as the heart thumps.
• D) the change in pressure in the blood vessels after the ventricles contract.

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Definitions:

Visual Perception

The process by which the brain interprets and makes sense of visual stimuli or images seen by the eyes.

Trichromatic Theory

A theory of color vision proposing that the human eye has three types of receptors with differing sensitivities to different light wavelengths, corresponding to red, green, and blue.

Afterimages

Visual phenomena where an image continues to appear in one's vision after the exposure to the original image has ceased.

Colorblindness

A visual impairment in which an individual has difficulty distinguishing between certain colors, usually between red and green, due to absent or defective color-sensitive cells in the eyes.