Slides in this set
Endocrine Key Words
Hormone: Molecules that are released by the endocrine glands directly into
blood, they act as messengers to carry signals to specific target organ/ tissue.
Endocrine gland: Secrete hormones directly into blood, it has no ducts.
Exocrine gland: Secretes molecules into a duct that carries them to the sit of use.
Target cells: Possess a specific receptor on cell surface membrane which is
complementary to the hormone's shape.
Adenyl cyclase: Enzyme associated with the receptor for many hormones,
including adrenaline. Found on the inside of the cell surface membrane.
First messenger: Hormones that transmit a signal around the body.
Second messenger: Is cAMP. Transmits a signal inside a cell.…read more
How does adrenaline work?
Protein, peptide and amino acid derivatives (adrenaline)are not soluble so
they can't enter the cell.
Must cause an effect inside the cell without entry. (Adrenaline is therefore the
The complementary receptor is associated with adenyl cyclase which is
activated when Adrenaline docks onto the receptor.
Adenyl cyclase converts ATP into cAMP, the 2nd messenger. CAMP activates
enzyme action inside the cell.…read more
Functions of the Adrenal glands
- Makes adrenaline which:
- Increases stroke volume of the heart
- Increases heart rate
- Dialate's pupils
- Cause body hair to erect.
- Makes steroid hormones:
- Mineralocorticoids= control concentrations of Na+ and
K+ in blood.
- Glucocorticoids= control metabolism of carbs and
proteins in the liver.…read more
Regulation of Blood glucose
Pancreatic duct: Tube that collects all secretions from exocrine cells in pancreas
carrying it all to the small intestine.
Islets of Langerhans: small patches of tissue that have an endocrine function.
Alpha cells: found in the iol and secrete glucagon.
Beta cells: found in iol and secrete insulin.
Insulin: hormone that causes blood glucose levels to drop.
Glucagon: hormone that causes blood glucose levels to rise.
Hepatocytes: liver cells, specialised to perform a range of metabolic functions.…read more