Unit 13: Endocrine System II Flashcards
__ adrenal glands resting above the kidneys
two
Adrenal gland consists of ______ and ______ tissue
glandular
neural
Inner _____ is composed of ______ tissue that is under control of the _ _ _
Medulla is composed of glandular tissue that is under control of the SYN
Outer cortex is under the control of the _______ ______. It is ______ in nature.
Pituitary hormones
endocrine in nature
Adrenal cortex layers
Zona glomerulosa
Zona fasciculata
Zona reticularis
Each layer contains a different _____ ______ that secretes a different ______ ______
cell type
steroid hormone
Aldosterone
Zona glomerulosa
Secreted in response to ANGII
low Na+ blood levels or high K+ blood levels
adrenocorticotropin hormone
Cortisol
Zona fasciculata
glucocorticoid hormone
helps with glucose metabolism
Androgen
Zona reticularis
secreted in response to ACTH
Medulla
Epinephrine
SYN
When stimulated by the SYN ______ is secreted into blood from the adrenal medulla
epinephrine
increases heart rate + force of contraction
blood flow to the heart and muscles
Cortisol: Always secreted…
I small amounts
Cortisol: _______ increases production and secretion
Stress
_ _ _ is secreted by the hypothalamus and stimulates the secretion of _ _ _ _ from the pituitary
CRH
ACTH
_ _ _ _ travels through the bloodstream to the adrenal glands and stimulates the release of cortisol from the zona ______.
ACTH
Fasciculata
________ can feedback into the hypothalamus and _____ the release of _ _ _.
cortisol
inhibit
CRH
Cortisol molecule
Hydrophobic steroid hormone
diffuses into the cell and attaches to receptors in the cytoplasm
cortisol-receptor complex translocates to the nucleus of the cell and alters activity of the cell
Cortisol concentration ________ throughout the day due to the ______ ______.
Varies
circadian rhythm (metabolic cycle)
During the day
Low Cortisol levels
Spike
At around 4am
just before waking up
due to hunger; preparation for the day
Glucocorticoid
involved in glucose metabolism
protects against hypoglycemia
catabolic; causes the breakdown of complex molecules
catabolisis maintains blood glucose levels
Cortisol Effects
surpresses immune systems
Cortisol effects: Liver
increased gluconeogenesis
Cortisol effects: skeletal muscles
decrease in protein synthesis
increase in the breakdown of proteins
decrease in glucose uptake
Cortisol effects: Adipose tissue
- decrease in lipid synthesis
- increase in lipolysis
- increase in fat deposits in the abdomen + cheeks
Cushing syndrome
excess cortisol wasting of muscles poor wound healing fat deposits in cheek and abdomen depression
Pancreas: parallel to and ______ the ______
beneath
stomach
Pancreas contains
Endocrine tissue: secreting hormones into the blood
Exocrine tissue: secreting chemicals through a duct into the digestive tract
Endocrine portion
1-2 million pancreatic islets
Alpha cells
- 25%
- secrete glucagon
Beta Cells
- 60%
- Secrete insulin
Delta cells
- 10% of islets
- secrete somatostatin
Insulin
Protein hormone
secreted by beta cells
cause the body to store and rapidly take up glucose
secreted when blood glucose levels are high
a small increase is required
Storage of Glucose
In the liver and skeletal muscles as glycogen
______ + _____ + _____ _____ respond normally to insulin
- liver
- muscle
- adipose-tissue
a _______ in bg will decrease the release of insulin
decrease
Glucagon
works in opposition to insulin
increases bg concentration
secreted when bg levels drop and when AA levels in the blood are high
Glucagon stimulates the liver
- glycogenolysis
- gluconeogenesis
Secretion of glucagon is stimulated by
intense exercise
increase 4 to 5 times normal amount
Glucagon causes the release of ______ ______.
Fatty acids can be used by muscles as a source of fuel
_ _ _ stimulates glucagon secretion
SYN
Why are fatty acids preferred by working muscles?
glucose is not that permeable to the cell membrane in the absence of insulin
Somatostatin
Released in the digestive tract by the hypothalamus (GHIH)
Somatostatin is released from
the pancreas when blood glucose levels rise/ AA levels in the blood increase or when there is increased blood born fats
Somatostatin reduces the secretion
of glucagon and insulin
prevents extremely rapid storgae of food; makes it available for the body for a long period of time
Fasted individual: BG level
80-90 mg/100 ml of blood
1 hour after a meal
120-140 mg/100 ml of blood
return to normal due to insulin
Starvation
glucagon stimulated gluconeogenesis to help maintain blood glucose levels around 80-90 mg/100 ml of blood
Glucose
primary energy source for the brain, - retina
- cells of the g
Diabetes Mellitus
inability of the pancreas to secrete insulin
inability of the target cells to react to insulin is in the blood
uptake and utilization of glucose by the cells of the body is dramatically decreased except for at the brain
dramatic increase of bg
Type I diabetes
damage to insulin producing beta cells
Type I diabetes occurs around the age of
14
In type I diabetes the
immune cells attack and destroys insulin-producing beta cells of the pancreas
Glucose _____ __ taken up by the cell (TID)
not taken up
bg rises to 300-1200 mg/ 100 ml of blood
Cells must rely on ___ + _____ _____ as a food source
fats
amino acids
Consequences of Type I Diabetes
glucose in urine
dehydration caused by increased glycose in the urine
more glucose in the filtrate reduces the amount of water reabsorbed by osmosis: more is excreted in the urine
Damage to blood vessels
Metabolic acidosis
depletion of protein stores
Damage to blood vessels
- leads to tissue damage
- eyes
- heart attack and stroke
- kidney damage
- nervous system damage
Metabolic acidosis
accumulation of acids from the breakdown of fats
Type II diabetes
80-90% of all diabetes
onset after 50 yoa
insulin has little effect on the cells throughout the body
cells are resistance to insulin’s uptake and storage effect
increase in bg level
decreased insulin release in later stages of disease
treated by a change in diet+weight loss
