Opening and Closing of the Heart Valves Is Caused by ________

question 33

Multiple Choice

Opening and closing of the heart valves is caused by ________.

• A) breathing
• B) gravity
• C) valves contracting and relaxing
• D) osmotic gradients
• E) pressure gradients

---

Definitions:

Pancreas

An organ in the abdominal cavity with roles in both digestion and the production of insulin and other hormones.

Electroencephalograph (EEG)

A diagnostic tool that records the electrical activity of the brain using small, flat metal discs attached to the scalp.

Positron-Emission Tomography (PET)

Positron-Emission Tomography, or PET, is a sophisticated imaging technique that uses radioactive substances to visualize and measure changes in metabolic processes and other physiological activities in the body.

Brain Activity

The functioning of the brain involving electrical, chemical, and neuronal processes contributing to thoughts, feelings, and behaviors.