Homeostasis

If the environment gets cold, we will often shiver in order to:

• decrease body temp

• to keep the body temperature the same as the external temperature

• increase body temp

• regulate blood pressure

Homeostasis in the human body is often maintained by a:

• positive feedback loops

• negative feedback loops

• neural feedback loop

The lungs and respiratory system are important to human homeostasis. When red blood cells enter the lungs,

• carbon dioxide leaves red blood cells and oxygen enters red blood cells (simple diffusion allows for this to happen)

• oxygen leaves red blood cells and carbon dioxide enters red blood cells (simple diffusion allows for this to happen)

• carbon dioxide and oxygen enter red blood cells (simple diffusion allows for this to happen)

Normally, when the concentration of glucose in the blood falls below a certain level, stored glucose reenters the blood until the original concentration is reached again. This regulation of the concentration of blood glucose is part of the process known as

• homeostasis

• respiration

• pinocytosis

• synthesis

The human body maintains glucose (a sugar/food energy) concentration in the body. After being digested, glucose sugar enters the bloodstream. Glucose can only enter the cells if __ is present. (This molecule regulates the amount of sugar in the cells.)

• insulin

• starch

• oxygen

• carbon dioxide