In this video, learn the names for the basic parts of the heart and the major blood vessels, as valves, as well as the direction of blood flow.

The main organs of the digestive system include the mouth, the esophagus, the stomach, the small intestine, and the large intestine. The mouth softens the food into a bolus, which is moved, via peristalsis, down the esophagus and into the stomach. Three layers of muscle churn the food into a uniform mixture called chyme. Parietal cells form HCl, which activates the enzyme pepsin and begins protein digestion.

This video describes how the electrical signal passes through the heart and causes the coordinated contraction of heart muscle. Also included is an explanation of an electrocardiogram (ECG).

How CSF is made and circulates around the brain. Role of arachnoid villi.

How CSF is made and circulates around the brain. Role of arachnoid villi.

CNS, PNS, sensory, motor, somatic motor, autonomic motor, and sympathetic and parasympathetic nervous system.