Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Endocrine System BDS1 > Calcium > Flashcards

Calcium Flashcards

1
Q

what are the functions of calcium?

A

bone and tooth structure, mineral store, action potentials, membrane excitability, 2nd messenger, co-factor in metabolic pathways, blood clotting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are the 2nd messenger functions of calcium?

A

muscle: excitation-contraction coupling, gland secretion, non-steroid hormone action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is diffusible calcium?

A

ionised calcium and calcium bound to citrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is non-diffusible calcium?

A

calcium bound to protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

how does calcium enter the body?

A

diet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

once in the body where are all the places that calcium goes?

A

GI tract, plasma and interstitial fluid, exchangeable bone, stable bone, kidney

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

how does calcium leave the body?

A

faeces and urine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what controls calcium homeostasis?

A

parathyroid hormone, calcitonin, vitamin D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

where is the parathyroid hormone secreted from?

A

parathyroid glands in response to low plasma calcium concentration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

how does the parathyroid hormone increase plasma calcium?

A

increase resorption of bone (osteoclasts), increase calcium resorption in kidney (with phosphate resorption), increase uptake of calcium from the intestines (assisted by vitamin D)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

where is calcitonin secreted from?

A

thyroid glands in response to high plasma calcium concentrations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

how does calcitonin decrease plasma calcium?

A

increase formation of bone (osteoblasts), decrease calcium resorption in kidney

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

how does vitamin D get into the body?

A

dietary vitamin D and 7-dehydrocholesterol synthesised in the skin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

how does vitamin D affect calcium in the intestine?

A

promotes calcium absorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

how does vitamin D affect calcium in the kidney?

A

promotes calcium retention and phosphate retention

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

how does vitamin D affect calcium in the bone?

A

promotes calcium release and phosphate release

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

how does vitamin D affect calcium in plasma?

A

promotes increased levels of calcium and phosphate due to the actions on the intestine, kidney and bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what hormones increase bone formation and bone mass?

A

calcitonin, growth hormone, IGF-1, insulin, oestrogen, testosterone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what hormones increase bone resorption and decrease bone mass?

A

cortisol, PTH and thyroid hormones

20
Q

what is the function of osteoblasts

A

synthesise and secrete collagne fibres forming a matrix later mineralised by calcium salts

21
Q

what are osteocytes?

A

trapped osteoblasts in the bone matrix

22
Q

where are the osteocytes?

A

lie within the bone lacunae and contact other cells via long cytoplasmic processes

23
Q

what are osteoclasts?

A

large, multinucleate cells, dervied from macrophages that resorb bone

24
Q

where do osteoclasts lie?

A

lie in depressions

25
Q

what is hypercalcaemia?

A

raised calcium concentration

26
Q

what is hypocalcaemia?

A

reduced calcium concentration

27
Q

what is hypocalcaemic tetany?

A

decreased calcium concentrations

28
Q

what is the cause of hypocalcaemic tetany?

A

decreased calcium intake, excessive calcium loss, alkalosis

29
Q

what does low calcium lead to?

A

increased nerve excitability

30
Q

what are the signs of increased nerve excitability?

A

pins and needles, muscle spasms

31
Q

how do you combat hypocalcaemia?

A

trap CO2 in the patients lungs which is achieved by rebreathing expired air from a bag

32
Q

what is osteitis fibrosa cystica and what is it a result of?

A

areas of demineralisation in skull and leg bones and is a result of hyperparathyroidism

33
Q

what is hypoparathyroidism

A

defective mineralisation of teeth due to low blood calcium levels due to undersecretion of PTH

34
Q

what is vitamin D deficiency?

A

dietary deficiency, failure to synthesise in body, decreased calcium uptake from GI tract, undermineralised bone

35
Q

what are bones like in a patient with a vit D deficiency?

A

undermineralised and lacks rigidity

36
Q

what is the vitamin D deficiency bone disease in children?

A

rickets

37
Q

what is the vitamin D deficiency bone disease in adults?

A

osteomalacia

38
Q

why is calcitonin not essential for the regulation of plasma calcium?

A

because increased or decreased levels of calcitonin do not have any clinical consequences

39
Q

what is osteoporosis?

A

decreased bone mass and density

40
Q

what is osteopetrosis?

A

increased bone mass and density

41
Q

what can be seen in patients with osteoporosis?

A

fractures are common

42
Q

what category of people is osteoporosis common?

A

the elderly but affects women earlier than men because of menopause

43
Q

what are the causes of osteoporosis?

A

menopause, corticosteroids, nutritional deficiency

44
Q

what happens to blood supply in patients with osteopetrosis?

A

it is reduced

45
Q

what are the effects of osteopetrosis?

A

prone to fracture and chronic infection

46
Q

what are the dental consequences of osteopetrosis?

A

difficult extractions, tooth roots indistinct on radiographs, mandible is bigger than maxilla

Endocrine System BDS1 (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions