| A | B |
|---|
| hormone | substance secreted by cells that act to regulate activity of other cells in body |
| endocrine gland | specialized cells that secrete hormones into blood or extracellular fluid |
| steroid hormone | substance derived from cholesterol; can diffuse through cell membrane of target cells |
| target cell | specific cell to which hormones bind to produce a specific effect |
| receptor | proteins on cells that bind to signal molecules that cause a cell to respond |
| prostaglandins | hormones produced by body tissues that act locally |
| kidney | organ that filters water and wastes from blood; makes urine |
| digestion | breaking down of food into chemical substances that can be used for energy |
| villus | tiny projection from cells increasing surface area of lining of small intestine |
| alveolus | tiny air cells where O2 and CO2 are exchanged in the lungs |
| diaphragm | main muscle in respiration |
| homeostasis | maintaining a stable internal environment |
| pathogen | infectious agent; organism that causes disease |
| pancreas | organ that releases sodium bicarbonate to neutralize stomach acids; releases enzymes to break down organic compounds |
| liver | produces bile to break down fats in digestion; also has detox functions |
