HORMONAL REGULATION OF GROWTH, DEVELOPMENT, & METABOLISM Flashcards
whats he pituitary gland
the anterior and posterior pituitary make up the two lopes of the gland.
what the anterior do
the anterior lobe makes and releases six major hormones:
1. TSH thyroid stimulating
2. ACTH
3. PRL (adrenal gland->glucocorticoids
4. HGH human growth
5. FSH reproductive
6. LH reproductive
what does posterior lobe do
does not produce any hormones and part of nervous system
what is does is it stores and releases adh and oxytocin which are made by the hypothalamus
whats the human growth hormone
produced by anterior pituitary
stimulates growth in children and adolescents
- influences many physiological processes
- increases protein synthesis
- stimulates cell division and growth
- stims metabolic breakdown and release of fats
what does hgh do
the hgh affect almost every boy tissue directly or indirectly, and majority of hgh effects are tropic.
- causes the liver to release growth factors which increase amino acid uptake by cells and protein synthesis
- stimulate cells to grow and divide
increase fat metablosim
if the pituitary gland secrete excess amount of hgh during childhood, it can result in gigantism. too low hgh result in pituitary dwarfism.
hgh in adultary can lead to acromegaly. since skelatal growth completed in adulthood, hgh results in widening of bones
the thyroid gland
lies below the larynx and has two lobes.
- known as metabolic thermostat bcuz the hormones it secretes regulate metabolic rates
- produces and secretes thyroxine which is a hormone that increases the rate at which the body metabolizes fats, proteins, and carbs for energy. thyroxine stims cells in the heart, skeletal muscles, liver, and kidneys to increase cellular respiration.
what is hypothyroidism
hypothyroidism is low production of thyroxine and can result in cretinism which are ppl that are stocky and shorter than average
hormonal injections required in childhood so that mental developments delay dont occur and adults with hypothyroidism experience fatigue and weight gain due to a slow metabolism
whats hyperthyroidism
hyperthyroidism is overproduction of thyroxine and symptoms can incldue anxiety, insomnia & weight loss.
can be treated with medication or removal of part of thyroid gland and can result in graves disease which is when the immune system atacks the thyroid gland
waht are goiters
the thyroid gland requires iodine to make thyroid hormones, if that isnt present, thyroxine cant be made an there will be no signal to stop TSH secretion, constant stim of thyroid causes a goiter.
calcium homeostasis
calcium is essential for nerve conduction, muscle contraction, skeletal development, and healthy teeth.
calcium levels in the blood are regulated in NEGATIVE FEEDBACK by two hormones: calcitonin and parathyroid hormone PTH).
when blood calcium levels are too high, the thyroid gland secretes calcitonin to promote uptake of calcium by the bones.
when blood levles are too low, the parathyroid glands release PTH. pth stimulates bones to break down bone material and secrete calcium into the blood.
PTH also stims the kidneys to reabsorb calcium from the urine. calcium reabsorption activates vitamin d and that stims the absorption of calcium from food in the intestine.
