M5 C14: hormonal communication Flashcards
what is the endocrine system?
where hormones are secreted by glands that are used to send information to bring about a response.
what are steroid hormones?
lipid soluble so can pass through membrane and bind to receptors in the nucleus
what are non steroid hormomes?
hydrophilic so cant pass through bilayer and bind to receptors on outside of cell
where are steroid hormones made?
Cortex
what is the medulla part of the adrenal gland?
neuronal function
where is the adrenal gland in the body?
Above the kidney
what neurotransmitters does the medulla secrete?
adrenaline, noradrenaline
both increase heart rate, blood pressure, slows metabolic rate, validation near muscles
what steroid hormones are made in the cortex?
mineralcorticoids
glucocorticoids
androgens
what are mineralcorticoids?
aldosterone- blood pressure, osmotic balance
what are glucocorticoids?
cortisol which regulates metabolic rate
what are androgens?
sex hormones eg estrogen
where is the pancreas?
upper abdomen directly behind the stomach.
what is the 2 main functions of the pancreas?
an exocrine gland and an endocrine glad.
what is the pancreas next to?
duodendum
what does the duodendum do?
enzymes are released into here by the pancreas eg ligase, amylase, these travel along the pancreatic duct
what is the endocrine role of the pancreas?
insulin, glucagon are made in the pancreas
what are the Islets of Langerhans?
Small regions of endocrine tissue that are responsible for producing insulin and glucagon.
What color are the beta cells stained using a differential staining technique?
Blue
What color are the alpha cells stained using a differential staining technique?
Pink
Fill in the blank: Using a differential staining technique, the beta cells are stained _______.
blue
Fill in the blank: Using a differential staining technique, the alpha cells are stained _______.
pink
What is the primary function of insulin?
Decreases blood glucose levels.
What is the primary function of glucagon?
Increases blood glucose levels.
Which cells in the pancreas secrete insulin?
β cells (in islets of Langerhans).
Which cells in the pancreas secrete glucagon?
α cells (in islets of Langerhans).
What effect does insulin have on glucose uptake?
Regulates the placement of channel proteins in the surface membrane of target cells so more glucose is absorbed from the blood. involved in glycogenesis converting glucose to glycogen
What processes are activated by glucagon to increase blood glucose levels?
Glycogenolysis- breakdown of glycogen to glucose
gluconeogenesis- production of glucose from non-carbohydrate sources.
What is glycogenesis?
Production of glycogen from glucose.
This process is stimulated by insulin, promoting glucose storage.
What is gluconeogenesis?
Production of glucose from non-carbohydrate sources.
This process is stimulated by glucagon, especially during fasting.
What is glycogenolysis?
Breaking down of stored glycogen into glucose.
This process is stimulated by glucagon when blood glucose levels are low.
True or False: Insulin is a globular protein composed of 51 amino acids.
True.
Insulin’s structure allows it to be soluble in water and function effectively in the bloodstream.
what is glucagons strucutre?
coiled ribbon secondary strucutre
What is the normal blood glucose level?
90 mg/100 cm³ blood.
Maintaining this level is crucial for metabolic functions.
When blood glucose levels rise, which cells detect this change?
Beta cells of the pancreas.
They respond by secreting insulin to lower blood glucose levels.