6.2 Physiology of the Endocrine System Part 3

Question 1

What is the action of thyroxin?

Answer 1

increases the metabolic rate in all cells
increases the number of respiratory enzymes
increases oxygen uptake

Question 2

What is thyroxin necessary for?

Answer 2

growth and development

Question 3

What is hyperthyroidism?

Answer 3

low thyroid function

Question 4

What are symptoms of congential hyperthyroidism?

Answer 4

reduced skeletal growth
sexual immaturity
abnormal protein metabolism

Question 5

What does the abnormal protein metabolism caused by hyperthyroidism lead to?

Answer 5

intellectual disability

Question 6

Where is calcitonin produced?

Answer 6

thyroid gland

Question 7

What is the function of caltitonin?

Answer 7

lowers the level of calcium in the blood and deposits calcium into bone

Question 8

Which hormone does calcitonin oppose the action of?

Answer 8

parathyroud hormone

Question 9

How many parathyroid glands are there and where are they located?

Answer 9

four
embedded into the surface of the thyroid gland

Question 10

What hormone does the parathyroid glands produce?

Answer 10

parathyroid hormone

Question 11

What is the function of PTH?

Answer 11

increase calcium levels in the blood
decrease the phosphate levels in the blood

Question 12

How does PTH increase calcium levels in the blood?

Answer 12

stimulates the increased absorption of calcium in the small intestine
retains calcium by excreting phosphate in the kidneys
promotes the activity of osteoclasts to demineralize bone

Question 13

When do the parathyroid glands stop producing PTH and how?

Answer 13

when calcium levels reach an appropriate amount in blood
negative feedback

Question 14

What occurs if PTH is not produced in response to low blood calcium levels?

Answer 14

tetany

Question 15

What are the symptoms of tetany?

Answer 15

body shakes from continuous muscle contraction

Question 16

How does calcium play a role in tetany?

Answer 16

low blood calcium causes an increased excitability of the nerves which will fire spontaneously and without rest

Question 17

What are the inner and outer portions of the adrenal glands called?

Answer 17

inner = medulla
outer = cortex

Question 18

How are the medulla and cortex “connected”?

Answer 18

hormonally; no physiological connection

Question 19

What does the adrenal medulla secrete?

Answer 19

epinephrine and norepinephrine

Question 20

When does the adrenal medulla secrete epinephrine and norepinephrine and where?

Answer 20

under conditions of stress
directly into the bloodstream