The __________ receives input from higher brain centers and sends nerve impulse to the respiratory centers in the medulla oblongata to modify the breathing pattern.

Worn-out red blood cells are removed from circulation by the _________ and ___________.

A nutrient that the body cannot synthesize, but instead must get from a balanced diet, is said to be ____________.

Antibodies that attack pathogens are produced by ______.

The healthy level for hematocrit in females is _____.

The end products of fat digestion are converted into ________ within epithelial cells and move into the ________ of villi.

B cells that respond to the same antigen and are derived from a single cell are referred to as ______.

Only lymphocytes possessing ________ that can bind with the ________ on an invading pathogen are involved in the immune response against it.

The most superior portion of the stomach is the __________.

________, a localized response to infection, attracts leukocytes to the affected tissues to destroy the pathogens.