Physiology Flashcards
(21 cards)
Endocrine glands will usually contain ducts. True/false?
False - ductless glands
What are the major endocrine organs?
Pituitary Thyroid Parathyroid Adrenal Pancreas Ovaries Testes
What are the hormone classifications?
Amines
Steroids
Peptides
Proteins
Describe autocrine signalling
The cell is both the signalling and target cell
Describe paracrine signalling
Signalling cell releases its signalling molecules which diffuse and meet target cells
Describe endocrine signalling
Signalling cell releases its molecules into the blood
Give an example of a complementary hormone action
Adrenaline, cortisol and glucagon all contribute to short term-exercise
Give an example of an antagonistic hormone action
Insulin works to lower blood sugar while glucagon works to increase it
Only steroid hormone not bound to protein is active. True/false?
True
Give some examples of carrier proteins
Cortisol-binding globulin
Thyroxine-binding globulin
Albumin
How do carrier proteins help to act as a hormone buffer?
Only free hormones can activate receptors meaning excess hormone is bound to by carrier protein
How does cortisol regulate its own secretion?
As it is carried back to the anterior pituitary and hypothalamus and suppresses release of the hormones involved in its secretion
The half-life of amines is seconds/minutes/hours?
Seconds
The half-life of steroids is seconds/minutes/hours?
Hours
The half-life of peptides is seconds/minutes/hours?
Minutes
What are the cell surface hormone receptors?
G-protein coupled receptors (GPCR)
Receptor kinases
What are the intracellular receptors?
Nuclear receptors
Class I nuclear receptor is activated by lipids/steroids and is found in the nucleus/cytoplasm?
Steroids
Cytoplasm
Class II nuclear receptor is activated by lipids/steroids and is found in the nucleus/cytoplasm?
Lipids
Nucleus
What activates hybrid class nuclear receptors?
Thyroid hormone (T3)
Insulin binds via what type of receptor?
Receptor kinases
