The Endocrine Glands Flashcards
What are the main types of hormones
Protein and glycoprotein homones - insulin, PTH
Small peptide hormones - vasopressin, oxytocin
Hormones derived form amino acids - thyroxin, adrenaline
Steroids devrived form cholesterol - testosterone, cortisol
What are diffuse endocrine systems
Scattered cells in organs that fulfil enteroendocrine cells of gut
Often paracrine role
Act locally
What are some examples of endocrine glands
Hypothalamus Pituitary Pineal Thyroid Parathyroid Thymus Adrenal Pancreas Goads
Where is the pituitary and what is it aka
Aka hypophysis
Sits in sella turcica of sphenoid bone
Just below hypothalamus
What is the division of the pituitary
Anterior - adenohypophysis - glandular
Posterior - neurohypophysis - nervous tissue
What is the hypothalamic-hypophyseal portal system
Attach ant pot to hypothalamus
What are the hypothalamic hormoene that region any pit
Ghrh Somatostatin Trh Crh Prolactin inhibi hormoene - dopamine GnRH
What are the cell types of the ant pit and what does it prod
Somatotrophs - GH Thyrotrophs - TSH Corticotroohs - acth Lactotrophs - prolactin Gonadotropin - FSH and LH
What does the ant pit consist of
Packed sec cells interspersed with fenestrated endothelium lined vasc sinuses
What are acidophilus
Basophils
Chormoohobes
Acidophils - stain acid dye somatotrophs and lactotrophs
Basophils - stain with basic dye thyrotrophs, corticotrophs, gonadotrophs
Chromophobes - stain very weak of either
What is in the post pit
Consists of axons of nerve cells in supraoptic and para ventricular nuclei of hypothalamus
Special glial cells pituicityes
What is the functional unit of the thyroid
Thyroid follicle filled with colloid
What does the follicle colloid contain
Iodothyroglobulin
T3 and t4
What are the thyroid c cells
C cells / parafollicular
Adjacent to follicular cells
In basal lamina easy to see with calcitonin
What is calcitonin
Inhibits osteoclast activty and lowers blood calcium
Where are the parathyroid glands
4 small oval glands
Posterior surface of thyroid gland
What do the parathyroid glands produce
PTH increases serum calcium by
Stim release calcium from bone
Increasing renal calcium reabs
Increasing calcium abs from gut
What are the three cell types in the parathyroid glands
Chief cells - sec PTH
Oxyphils - large mitochondria not sure what prod
Adipose cells
What is the structure of the adrenal glands
Adrenal cortex - formed with epi cells
Adrenal medulla - formed of neural crest made adrenaline. Or noradrenaline symp nerve fibres
Adrenal glands surrounded by thick capsule with connective tissue
What are the three distinct layers of the adrenal cortex
Zona glomerulosa
Zona fasciculata
Zona reticularis
What are mineralcorticoids
From zona glomerulosa - aldosterone which promotes sodium retention
What are glucocorticoids
Zona fasciculata - cortisol stress hormone
What are the sex hormones
Androgens zona reticularis
Hat are the three endocrine pancreas hormones
Insulin sec cells form beta cells
Glucagon secreted form aloha cells
Somatostatin form delta cells
What cells produces testosteron in testes
Leydig cells
What are the the a interna
Cells surrounding the developing ovarian follicle are responsible for female sex hormone s
What are the main functions of the endocrine system
Maintain body homeostasis
Help body to react to stress in concert with the nervous system
Regulate growth and development, including sexual development and reproduction
