Chapter 16 Endocrine System Flashcards
Amino acid based hormones
Most hormones
Water soluble
Cannot cross plasma membrane
Steroid hormones
Only gonadal and adrenocortical hormones are steroids
Synthesized from cholesterol
Lipid soluble
Can cross plasma membrane
How is hormone release regulated?
Negative feedback mechanisms
endocrine gland stimuli types
Humoral stimuli - blood contents
Neural stimuli - response to stress
Hormonal stimuli - other hormones
What is up-regulation?
Target cells forming additional receptors for a hormone
What is down-regulation?
Target cells decreasing receptors for a hormone as a result of prolonged exposure
Three types of hormone regulation
- Permissiveness - hormone needs another hormone present to act fully
- Synergism - two hormones with the same effect amplify actions
- Antagonism - When one hormone opposes the actions of another
Posterior Pituitary hormones
- Oxytocin
- Antidiuretic hormone
- Stimulates uterine contractions and ejection of breast milk
- Stimulates kidneys to reabsorb water
Anterior Pituitary hormones
- Adrenocorticotropic hormone
- Follicle-stimulating hormones
- Luteinizing hormone
- Adrenal cortex: promotes release of glucocorticoids and androgens
- Stimulates ovarian follicle maturation and production of estrogens, sperm production
- Triggers ovulation, estrogen and progesterone production, testosterone production
Thyroid gland 2 hormone types
- Thyroid hormone - incr. body heat, regulates tissue growth and development, maintaining blood pressure
- Calcitonin - no known physiological roles in humans, bone preserving.
What does the thyroid gland control?
Metabolism
What do the parathyroid glands regulate?
Blood calcium levels
Adrenal glands produce hormones hormones involved in ______ ______ and the _____ _______.
Electrolyte balance, stress response
Adrenal cortex hormones
- Mineralocorticoids
- Glutocorticoids
- Gonadocorticoids
- Regulate electrolyte concentrations in extracellular fluid
- Influence energy metabolism of most cells and help resist stressors
- Contribute to axillary and pubic hair development
Functions of melatonin
Influences sleep, body temp, appetite.
Two main pancreatic hormones
- Glucagon
- Insulin
- Breakdown of glycogen to glucose, synthesis of glucose, raising blood glucose levels.
- Lower blood glucose, inhibits breakdown of glycogen to glucose
Ovaries produce estrogens and progesterone, which function to:
Maturation of reproductive organs, secondary sex characteristics, menstrual cycle.
The testes produce testosterone, which function do:
Mature male reproductive organs, secondary sec characteristics, libido.
Adipose cells release…
Leptin, which controls appetite
Enteroendocrine cells release hormones that…
assist with digestive functions
Atrial natriuretic peptide (ANP) functions
Decreases blood pressure, inhibit sodium ion reabsorption
Erythropoietin (Kidney) function
Stimulates production of RBC in red bone marrow
Osteocalcin functions
Increases insulin production and sensitivity
Cholecalciferol (Skin) function
Stimulates active transport of calcium across cell membranes of small intestine
Thymus hormones functions
Involved in T lymphocyte development, immune responses
