Increased pressure in the aorta triggers mechanisms to lower blood pressure.

A rise in estrogen during the menstrual cycle increases the number of progesterone receptor in the uterus.

Increased blood sugar stimulates the release of a hormone from the pancreas that stimulates the liver to store blood sugar.

A rise in blood calcium levels triggers the release of a hormone that lowers the blood 

When a nervous stem cell differentiates into a neuron versus a neuroglial cell.

When the high level of a substance decreases the production and secretion of a hormone.

When an injury activates a few platelets that lead to the activation of thousands of plasma fibrinogen until a blood clot is formed.

When the cardiovascular, respiratory, urinary, nervous and endocrine systems coordinate to maintain blood pH between 7.35 and 7.45.

When the body attenuates sudden significant changes so that most indicators fluctuate within a narrow range around a set value.

When an organism has a particular characteristic that makes them better suited for a particular function.

When changes in an organism accumulate over generations such that they become better suited to their environment.

When changes in behavior are prompted by an event in the organism’s environment.