Control the internal environment of the body from the cellular level to the organ level of organization
Control cellular respiration, cellular growth, and cellular reproduction
Control the fluids in the body such as water amounts and balances of electrolytes
Control the secretion of other hormones
Control our behavior patterns
Play a vital role in the reproductive cycles of men and women
Regulate our growth and development cycles
Homeostasis is preserved through intercellular communication by the nervous and endocrine systems
Classes of hormones
Lipid-soluble hormones
Protein and peptide hormones
Lipid-soluble hormones
Steroid hormones
Thyroid hormones
Protein and peptide hormones
Polypeptide hormones
Glycoprotein hormones
Thyroid hormones
Thyroxine (T4)
Triiodothyronine (T3)
Parathyroid hormones
Parathyroid hormone (PTH)
Pancreas
Insulin
Glucagon
Other glands and hormones they secrete
Pineal gland - Melatonin
Adipose tissue - Leptin
When a cell receives instructions from two hormones at the same time, four outcomes are possible: opposing/antagonistic effects, additive/synergistic effects, permissive effects, and complementary/integrative effects
The hormonal responses to stress
1. Alarm phase
2. Resistance phase
3. Exhaustion phase
Behavioral effects of specific hormones are most clearly seen in individuals whose endocrine glands are oversecreting or undersecreting, although normal changes in circulating hormone levels can also cause behavioral change
In elderly people, smaller amounts of GH and insulin are secreted after a carbohydrate-rich meal
