HPA

Question 1

What are the typical 4 features of a feedback mechanism?

Answer 1

1-System variable
2-Set point
3-Detector
4-Corrective mechanism

Question 2

What are 6 of the major hormonal contributors to homeostasis?

Answer 2

1-Thyroid hormone (basal metabolism)
2-cortisol (energy metabolism/stress response)
3-Mineralcorticoids (plasma volume)
4-Vasopressin(ADH) (plasma osmolalility via water excretion)
5-Parathyroid hormone (calcium and phosphorous level)
6-Insulin (glucose levels)

Question 3

What is a neurocrine hormone?

Answer 3

secretion by a neuron to the bloodstream

Question 4

What are the 3 chemical classes of hormones?

Answer 4

1-Steroid
2-Peptide/protein
3-Amine (tyrosine derivatives)

Question 5

What are the two general categories of hormones?

Answer 5

1-Lipophilic (non polar) fat soluble (bind intracellularly for response)
2-Hydrophilic (polar) water soluble (bind extracellularly for response)

Question 6

What are the two groups of hormones derived from tyrosine?

Answer 6

1-Thyroid hormone(bind nuclear receptors)

2-Catecholamines (bind surface receptors ie. epinephrine/norepinephrine)

Question 7

What is characteristic of Peptide/protein hormones?

Answer 7

• Water soluble
• most numerous
• often produce precursors that are cleaved post translationally to become active

Question 8

The _________ is formed in the ER before getting broken down to _____________ in golgi apparatus and then secreted as a __________

Answer 8

Preprohormone, Prohormone, hormone

Question 9

What 9 hormones are examples of having pro hormones?

Answer 9

• Somatostatin
• Insulin
• Glucagon
• Calcitonin
• ADH
• Gastrin
• Enkephalin
• Parathyroid Hormone
• ACTH

Question 10

How do hydrophilic hormones pass on their message?

Answer 10

binding surface receptors that use second messenger pathways to transduce the signal (often G proteins)

Question 11

What are steroid hormones derived from?

Answer 11

Cholesterol

Question 12

What is characteristic of Steroid hormones?

Answer 12

• Lipid soluble

- are carried by hormone specific plasma binding globulins in the blood (bound hormones act as a reservoir)

Question 13

Lipid soluble hormones cross cell membranes and form what?

Answer 13

Hormone receptor complexes that act as transcription factors to regulate the target gene

Question 14

What two feedback regulations happen with hormones?

Answer 14

• Negative feedback: Hormone down regulates

- Positive feedback: hormone up regulates (rare, partuition is the main example)

Question 15

What are the three lobes of the pituitary gland?

Answer 15

1-Anterior pituitary
2-Intermediate lobe/pars intermedia
3-Posterior pituitary

Question 16

What connects the hypothalamus to the pituitary?

Answer 16

Infundibulum

Question 17

How does the Hypothalamo-hypophysial portal system interact with the anterior pituitary?

Answer 17

Releases hormones into the capillaries that reach the anterior pituitary to either stimulate or inhibit secretion of hormones

Question 18

How does the Hypothalamo-hypophysial portal system interact with the posterior pituitary?

Answer 18

Oxytocin and ADH are synthsized by hypothalamus and transported to posterior pituitary for storage until needed.

Question 19

What is the HPA axis primarily associated with?

Answer 19

Stress

Question 20

Feedback loops ensure serum ___________ homeostasis

Answer 20

osmolalility (primarily through the kidneys)

Question 21

What are the three zones of the adrenal gland cortex and what does each zone secrete?

Answer 21

1-Zona glomerulosa- Mineralcorticoids
2-Zona Fasciculata- Glucocorticoids
3-Zona reticularis- Adrenal androgens

Question 22

The medulla of the adrenal gland is responsible for secreting what?

Answer 22

Catecholamines (epinephrine/norepinephrine) short term stress response

Question 23

What affect does aldosterone(mineralcorticoid) have?

Answer 23

promotes sodium reabsoroption and postassium excretion in renal collecting and distal tubules

Question 24

Cortisol works in a feedback loop to ___________ the HPA axis

Answer 24

inhibit

Question 25

What are the 3 main categories of endocrine disorders?

Answer 25

1-Endocrine gland hyposecretion
2-Hormone resistance
3-Hormone excess