Endocrine system & endocrine dysfunction Flashcards
The cells of endocrine glands:
release their secretions directly to the blood.
The most complex hormonal regulation responses involve the:
hypothalamus
The hypothalamus controls the anterior pituitary gland by:
secreting releasing & inhibiting hormones into a system of blood vessels connecting the two.
Increased levels of which hormone will lead to increased levels of calcium ion in the blood?
parathyoid hormone
The adrenal medulla produces
adrenaline
When blood glucose levels rise,
insulin is released.
When blood glucose levels fall,
glucagon is released.
Cells of the adrenal cortex produce:
aldosterone.
The pancreatic hormone that causes glucose to leave the blood and enter its target cells is:
insulin.
The hypothalamus acts as both a part of the brain and a(n) ________ organ.
endocrine
How would an elevated level of thyroid hormone in the body affect skeletal muscles?
It would stimulate energy use and heat production.
Which of the following hormones is released under the control of a positive feedback loop?
Oxytocin
Which of the following hormones is NOT controlled by the hypothalamus?
Parathyroid hormone
Prolonged stress reduces our immunity by:
increasing the release of cortisol.
Which of the following hormones would be expected to decrease inflammation and the associated pain?
Cortisol
If the pancreas was unable to produce insulin, what disorder would result?
Diabetes mellitus
A person undergoes surgery for a tumour of the thyroid gland. The surgery involves the removal of almost the entire gland. After the surgery, the patient’s plasma calcium levels were found to be chronically low. What would be the most likely reason for this?
The removal of the thyroid gland would have resulted in the removal of the parathyroid glands along with it. Since parathyroid hormone normally raises plasma calcium level, the plasma calcium level dropped after the surgery.
A person is suffering from tiredness, weakness and inability to tolerate cold temperatures. What is the endocrine problem likely to be?
Insufficient thyroid hormone
The type of feedback loop that produces stability and controls physiological values within a range is:
a negative feedback loop
You have had a busy day at work and have not had any lunch, so your blood sugar level has dropped. What hormone would you expect to be released in reponse to this drop?
Glucagon
A person is suffering from the following symptoms: dry mouth, indigestion, and a racing heart. It is discovered that the problem is due to overactivity in one of the divisions of the nervous system. Which division is it likely to be?
Autonomic sympathetic
A person is eating a diet rich in calcium, but is not absorbing much of the calcium. Which of the following could be used to correct this problem?
Vitamin D
Children who have been completely protected from sun exposure can get soft bones because:
Lack of sun exposure leads to low levels of vitamin D which results in low plasma calcium and removal of salts from the bone.
A young woman has had her pituitary gland removed. Which of the following will she now experience?
Hypothyroidism
What hormones are SECRETED BY THE HYPOTHALAMUS
- thyrotropin-releasing hormone (TRH)
- gonadotropin-releasing hormone (GnRH) 3. growth hormone-releasing hormone (GHRH, somatoliberin)
- corticotropin-releasing hormone (CRH)
WHAT IS RELEASED BY THE POSTERIOR PITUITARY
- Oxytocin
- Antidiuretic hormone (ADH)
WHAT IS RELEASED BY THE ANTERIOR PITUITARY
- Thyroid stimulating hormone (TSH)
- Gonadotropin
a. luteinizing hormone (LH)
b. follicle-stimulating hormone (FSH). - Growth hormone (GH, stomatotropin)
- Adrenocorticotropin (ACTH)
How does the endocrine system help the body achieve homeostasis?
the endocrine system uses the secretion of hormones for slower but longer-lasting regulation
What is a positive feedback loop?
Positive Feedback Loop: Amplifies or reinforces a response, moving away from the initial state.
Example: Childbirth contractions, where each contraction stimulates more contractions until delivery
What is a negative feedback loop?
Negative Feedback Loop: Stabilizes and returns the system to its original state, reversing the initial response.
Example: RAAS
Renin, Angiotensin, Aldosterone System
Low blood pressure/volume = release of renin = production of angiotensin = prodution of aldosterone = increase in blood volume/pressure via retention of water and sodium
What signals the realease of Aldosterone and which gland is it secreted from?
The adrenal cortex
CRH (corticotropin releasing hormone)
ACTH (adrenocorticotropin hormone)
What signals the realease of Thyrotropin and which gland is it secreted from?
The thyroid
TRH (thyrotropin releasing hormone)
TSH (thyroid stimulating hormone)
When the hypothalamus releases CRH what happens?
When corticotropin releasing hormone is released, it signals the pituitary to release adrenocorticotropin, which goes to the adrenal cortex and releases Cortisol and Aldosterone
What two hormones are released at the adrenal cortex and what do they do?
Aldosterone and Cortisol
Aldosterone increases sodium absorption;
Cortisol stimulates the sympathetic (fight or flight) system, increases BGL and supresses the immune system
What hormones does the thyroid release and what do they do?
T3 and T4 (thyroxine)
The increase matabolisim
What signals the realease of T3 and T4 and which gland is it secreted from?
The thyroid
TRH (thyrotropin releasing hormone)
TSH (thyroid stimulating hormone)
When the hypothalamus releases TRH what happens?
When the thyroid releases TRH (thyrotropin releasing hormone), the thyroid releases TH (thyroid stimulating hormone), which triggers the release of T3 and T4.
What signals the realease of Testosterone, progesterone and Oestrogen, and which gland are they secreted from?
The testes and ovaries
GnRH (Gonadotropin Releasing Hormone)
FSH/LH (Folicle Stimulating Hormone/Leutenising Hormone)
What organs are effected by by LH and FSH and how?
Prepares the uterus for pregnancy:
FSH - Folicle maturation - Oestrogen
LH - Stimulates Ovulation - Progesterone
Signals sperm production in the testes via testosterone:
FSH - Sertoli cells
LH - Leydig cells
What signals the realease of Prolactin and which gland is it secreted from?
The breasts
PRH (Prolactin Releasing Hormone)
What hormone is released by the thyroid and what do they do?
T3 and T4 (thyroxine) regulate metabolisim
What hormone regulates the calcium in the blood?
Parathyroid hormone
What hormones are released by the adrenal medulla?
Nor-adrenaline and adrenaline
What organ releases hormones to help with Blood Glucose Levels
The pancreas
What hormones does the pancreas release?
Insulin and Glucagon
What hormones stimulate the sympathetic nervous system and what releases them?
Cortisol and adrenaline, released by the adrenal glans
What symptoms would an increase of ACTH result in?
Increased:
Heart Rate
Blood Pressure
Respitory rate
Mental Clarity
Steroid hormones end in
one or ol
Aldosterone, corsisol
Amine hormones end in
ine
Epinephrine
Protein hormones end in
in
Insulin, oxytocin
