Most Sleeping Time Is Spent in

question 1

Multiple Choice

Most sleeping time is spent in

• A) REM sleep.
• B) stages 1 and 2 sleep.
• C) stage 4 sleep.
• D) very light sleep.

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Definitions:

Aortic Semilunar Valve

A valve in the heart located between the left ventricle and the aorta, preventing backflow of blood into the left ventricle.

Left Atrium

The upper left chamber of the heart that receives oxygenated blood from the pulmonary veins and pumps it into the left ventricle.

Frontal/Coronal Section

A type of anatomical view or slice that divides the body or organ into anterior and posterior parts.

Oblique Section

A slice made through a structure or tissue at an angle other than 90 degrees to its axis, providing a cross-sectional view.