5.4 hormonal comm Flashcards
How are hormones, secreted
They are released directly into the blood from endocrine glands.
They are transported by the blood and detected by target cells.
non-steroid hormones bind to the complimentary receptor on the plasma membrane of the targets cell and cause the release of the secondary messenger.
The secondary messengers stimulates a change in the activity of the cell
Structure and function of adrenal gland
adrenal medulla - scretes. Adrenaline and noradrenaline
adrenal cortex has 3 layers of cells:
zona glomerulosa - secretes mineralcorticoids
zona fasciculata - secrets glucocorticoids
zona reticularis - secretes prescuser molecules
Mineralocorticoids
help to control the concentration of sodium and potassium in the blood.
Endocrine and exocrine functions of the pancreas
exocrine - Produce pancreatic juice to deliver to small intestine
Endocrine- produce a hormone glucagon and insulin 
Histology of the pancreas
Islets of Langerhans produce hormones.
Two cell types:
Alpha cells secrete glucagon.
Beta cells secrete insulin
When blood glucose concentration is high…
Glycogenesis
Making glycogen from glucose
gluconeogenesis
conversion of amino acids and glycerol into glucose
glycogenolysis
converting glycogen to glucose
when blood glucose conc is too low…
releasing insulin
TYPE 1 VS TYPE 2
POTENTIAL TREATEMNTS
Stem cells to grow new islets of Langerhans in the pancreas
Genetically modifying E. coli to manufacture human insulin.
Advantages:
– exact copy of human insulin – fast acting more effective.
– less chance of developing tolerance to insulin.
- Less chance of rejection.
- Lower risk of infection
– cheaper to manufacture insulin, then extracting from animals
- more ethical
Aldosterone -
acts on collecting ducts in the kidney…. increases absorption of sodium ions and **decreases absorption **of potassium ions and increases water retention
Glucocorticoids
help to control the metabolism of carbohydrates, fats and proteins in the liver.
