Flow of Blood Backward from the Aorta into the Heart

question 88

Multiple Choice

Flow of blood backward from the aorta into the heart, caused by a weak heart valve, and is called:

• A) aortic regurgitation.
• B) myocardial infarction.
• C) myocardial ischemia.
• D) valvulitis.
• E) ventricular septal defect.

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Definitions:

Nitrogen-Fixing Bacteria

Microorganisms capable of converting atmospheric nitrogen into compounds usable by plants.

Sucrose

A disaccharide sugar composed of glucose and fructose, commonly known as table sugar, used by organisms as a source of energy and carbon.

Humus

The organic component of soil, formed by the decomposition of leaves and other plant material by soil microorganisms.

Silt

Fine granular material often found on riverbeds, composed of rock and mineral particles.