The Endocrine System Flashcards
What do Hormones do?
Regulate: Chemical composition of internal environment, Metabolism
Control of growth and development
Regulation of reproductive systems
Establishing and maintaining circadian rhythms
Anterior Pituitary Gland
Human Growth Hormone: Stimulates growth
Prolactin: Stimulates and maintains production of milk in breast tissues
Thyroid Stimulating Gland: Regulates thyroid activities
Follicle Stimulating Hormone
Leutenizing Hormone: Regulates activities in the ovaries and testes
Adrenocorticotropic Hormone: Regulates adrenal cortex activities
Melanocyte Stimulating Hormone: Stimulate melanocyte
Posterior Pituitary Gland
Oxytocin: Birth & nipple stimulation for breastfeeding
Antidiuretic Hormone:
Thyroid Gland secrets what hormones
Thyroxine (T4)
Triiodothyronine (T3)
Calcitonin (CT)
What do Thyroid hormones regulate
Oxygen use and metabolic rate
Cellular metabolism
Growth and development
Parathyroid Gland, Parathyroid Hormone maintains homeostasis of
Calcium (increased by PTH)
Magnesium (increased by PTH)
Phosphate (decreased by PTH)
Adrenal Glands consists of what cortex?
Consists of an adrenal cortex (outer) and adrenal medulla (inner)
The cortex is divided into three zones
Outer- mineralocorticoids
Middle- glucocorticoids
Inner- androgens
The medulla secretes epinephrine (adrenaline) and norepinephrine (NE) under stress
Adrenal Cortex Hormones
Mineralocorticoids: increase sodium (Na) and water reabsorption, and decrease potassium (K) reabsorption
–Secretion is controlled by the renin-angiotensin-aldosterone pathway
Glucocorticoids: breakdown protein and triglycerides, make glucose, have anti-inflammatory effects, and suppress immune responses
–Secretion is controlled by ACTH
Androgens: stimulate growth of axillary and pubic hair, contribute to puberty and have a role in libido
The Pineal Gland
Secretes melatonin which regulates the ‘body-clock’
The Pancreas has what functions? What do which cells produce?
Both endocrine and exocrine
Alpha cells secrete glucagon
Beta cells secrete insulin
Ovaries produce
Oestrogen
Progesterone
Inhibin
The female sex hormones regulate:
Menstrual cycle
Pregnancy
Lactation preparation
Female body shape
Testes produce
testosterone and inhibin
Testosterone:
Regulates production of sperm
Develops masculine characteristics
The Pineal Gland secretes
melatonin which regulates the ‘body-clock’
The Stress Response caused by what? What happens?
caused by a variety of disturbances to homeostasis: Heat or cold, Infection, Heavy bleeding, A strong emotional reaction
Fight-or-flight
-Initiated by the nervous system
-Impulses stimulate the adrenal medulla
-Activates the body for immediate ‘fight-or-flight’
The main organs are provided with glucose and oxygen
The brain
Skeletal muscles
The heart
The resistance phase
This continues once the immediate ‘fight-or-flight- response is over
Once the stressful event is over the body returns to normal
Exhaustion
This occurs where the body utilises all of its available resources during the resistance phase
