| Term | Definition |
| Homeostasis | Processes the body uses to maintain an internal balance. |
| Dynamic equilibrium | A condition that is stable within certain levels |
| Negative feedback | Processes that restore conditions to their original states (Resist change) |
| Positive feedback | Process that amplifies a small change (Reinforce change) |
| Thermoregulation | Maintenence of body temperature |
| Hypothalamus | Part of the brain that controls temperature |
| Growth hormone | Produced by the pituitary gland, stimulates growth in the body (also known as somatotropin) |
| Insulin | Hormone produced by the islets of Langerhans in the pancreas; secreted when blood sugar levels are high |
| Epinephrine | Produced in the adrenal medulla, accelerates heart rate and body reactions during a crisis |
| Cortisol | Stimulates conversion of amnio acids to glucose by the liver |
| Cyclic AMP | Secondary chemical messenger that directs the synthesis of protein by ribosomes |
| Thyroxine | Iodine-containing hormone produced by the thyroid gland, increases the rate of body metabolism and regulates growth |
| TSH | Stimulates release of thyroxine from the thyroid |
| ACTH | Stimulates release of hormones involved in stress responses |
| FSH | Stimulates follicle development of ovaries and development of sperm cells |
| LH | Stimulates ovulation and formation of the corpus luteum and stimulates the production of testosterone |
| Prolactin | Stimulates and maintains milk production in lactating females |
| Oxytocin | Initiates strong contractions during childbirth and triggers milk release in lactating females |
| ADH | Increases water reabsorption by the kidneys |
| Glucagon | Produced by the pancreas to convert glycogen to glucose when blood sugar is low |
| Adrenal medulla | Produces epinephrine and norepinephrine |
| Norepinephrine | Increases heart rate and blood sugar |
| Adrenal cortex | Produces glucocorticoids and mineralocorticoids |
| Glucocorticoids | Hormones produced by the adrenal cortex designed to help the body fight stress |
| Calcitonin | Lowers blood calcium levels |
| PTH | Raises blood calcium levels |