Endocrine System Flashcards
Where are hormones released into?
Bloodstream
How are the 2 ways that hormone negative feedback can go wrong?
- Target cell loses sensitivity to hormone
- Tumour suppresses endocrine gland and causes either too much or too little hormone
What are the main glands in the head?
Hypothalamus and pituitary gland (hypophysis)
What are the main glands in the neck?
4 parathyroid and thyroid glands
What are the main glands in the abdomen?
2 adrenal glands and the pancreas
What are the main glands in the female pelvis?
2 ovaries
What are the main glands in the male perineum?
2 testes
What is the diencephalon?
Thalamus and hypothalamus
Where is the pituitary gland found?
Midline structure in the pituitary fossa of the sphenoid bone
What cranial bone contains organs of hearing and balance?
Temporal bones
What does the infundibulum do?
Connects the pituitary gland to the hypothalamus
What is the neurohypophysis?
Posterior pituitary gland
The posterior pituitary gland is a continuation of what?
Hypothalamus
What hormones does the posterior pituitary gland secrete?
ADH and oxytocin
What do releasing hormones from the hypothalamus do?
Stimulate the anterior pituitary gland to release the appropriate hormone
What do release-inhibitory hormones from the hypothalamus do?
Prevent the anterior pituitary gland from releasing its hormone
What are some hormones (relative to what we have learnt) secreted by the anterior pituitary gland?
Growth hormone, thyroid stimulating hormone, adrenocorticotropic hormone,
What veins transport hypothalamic hormones?
Hypophyseal portal veins
An enlarged thyroid gland is a goitre. What is a dietary factor which can cause this?
Lack of iodine
What is used to manufacture T3 and T4 in the thyroid gland?
Iodine
What thyroid hormone can we not live without?
T3
What does parathyroid hormone control?
The amount of calcium in the blood and bone
Is parathyroid hormone under pituitary control?
No
What is the arterial supply to the thyroid?
Superior and inferior thyroid arteries
What is the venous drainage from the thyroid?
Superior, middle and inferior thyroid veins
The pancreas is a retroperitoneal structure overlying which vertebra?
L1/L2
What is the pancreas anterior to?
Aorta and IVC
What is the pancreas posterior to?
Stomach
What does the pancreas lie between?
Duodenum and spleen
What is the arterial supply to the pancreas?
Coeliac trunk and superior mesenteric artery
Where is the venous drainage from the pancreas to?
Splenic vein and superior mesenteric vein and into the hepatic portal vein
Is the pancreas under the control of the pituitary gland?
No
An exocrine glad secretes products where?
Into ducts- not directly into the bloodstream
What type of structure are the adrenal glands and where are they found?
Retroperitoneal- on top of the kidneys
What are the two anatomical and functional parts of the adrenal glands?
Outer cortex and inner (adrenal) medulla
What does the outer cortex of the adrenal gland produce?
Glucocorticoids, mineralocorticoids, androgens
Which of the hormones produced by the adrenal cortex is under pituitary control?
Glucocorticoids
What hormones are released from the inner medulla?
Adrenaline and noradrenaline
What do glucocorticoids do?
Influence metabolic rate of proteins, fats and sugars
What do mineralocorticoids do?
Regulate salt balance and impact on blood volume/pressure
What is the arterial supply of the adrenal glands?
Superior, middle and inferior suprarenal arteries (on left and right)
The middle suprarenal arteries are a branch of what?
Aorta
What inferior suprarenal arteries are a branch of what?
Renal artery
What is the venous drainage from the left and right adrenal glands and where do these drain to?
Left adrenal gland- left suprarenal vein which drains into the left renal
Right adrenal gland- right suprarenal vein into IVC
The inferior parts of the blood supply to the testis run within what?
Spermatic cord
What do the testes secrete?
Testosterone
What does testosterone control?
Male secondary sex characteristics
Closure of epiphyseal growth plates
Stimulate sperm
What do ovaries produce?
Oestrogen and progesterone
Do the testis and ovaries respond to the pituitary gland?
Yes
What does progesterone do?
Prepares the uterus for pregnancy
What does oestrogen do?
Female secondary sex characteristics
Ovum development
Where does the right gonad drain venous blood into?
IVC
Where does the left gonad drain venous blood into?
Left renal vein
