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Flashcards in Calcium Deck (67):
1

____ IS THE MOST ABUNDANT MINERAL IN THE BODY

CALCIUM!

2

about 99% of calcium in the body is found

in the bone and teeth

3

sources

dairy
seafood
veggies
figs
black strap molasses

4

_____ is the most potent inhibitor of calcium absorption and is found at high concentration in spincach and rhybabrb

oxalate (oxalic acid)

5

calcium is present in foods as relatively insoluble _____

salts

6

calcium can be solubilized at an _____pH

acidic

7

absorption of calcium occurs primarily in the SI and

two routes
1. duo and prox jeju
2. jeju and ile

8

1. absorption through the duodenum and proximal jejunum

cellular
active transport (req ATP)
saturable
involves calcium binding protein
stimulated by 1,25OH and low Ca levels

9

2. absorption through the jejunum and ileum

paracellular
passive diffusion- requires no energy
unsaturable
requires no carrier
stim- when high [ ] of Ca intracell and in lumen
stim by FOS

10

factors that enhance calcium absorption

growth pregnancy lactation
vitamin d
simple sugars
protein
food

11

factors that inhibit calcium absorption

oxalate
phytate
fiber
other divalent cations and minerals
fal maldigestion

12

Calcium is transported across the cytoplasm of the enterocyte bound to

CBP

13

calcium is transported from enterocyte into extracellular fluid by

Ca/Na ATPase

14

calcium is transported in the blood in three forms

free
proteins (albumin)
sulfate, phosphate, citrate

15

calcium levels in the___ and ___ must be maintained within a very narrow concentration range for normal physiological functioning

blood and extracellular fluid

16

extracellular calcium concentration or regulated by

PTH
calcitriol
calcitonin

17

___ plasma calcium levels stimulate PTH secretion and inhibit calcitonin secretion

low

18

PTH and calcitriol _____ plasma calcium

increase

19

PTH increases renal synth of calcitriol from ___

25-OH vit d

20

PTH and calcitriol increases renal tubular reabsorption of

calcium

21

calcitriol enhances intestinal ____absorption

calcium

22

PTH and calcitriol stimulate _____ activity

osteoclast

23

high plasma calcium levels stimulate ____ secretion, which _____ serum calcium levels

calcitonin, lower

24

calcitonin secretion inhibits _____activity which stimulates osteoblasts

osteoclasts

25

calcitonin inhibits ____ production which decreases calcium absorption and increases calcium excretion in the urine

calcitriol

26

Serum calcium

incr PTH
incr calcitriol
decr calcitonin

27

bone calcium

decr PTH
dec calcitriol
incr calcionin

28

renal calcium reabsorption

incre PTH
incr calcitriol
decr calcitonin

29

intestinal calcium absorption

no effect on PTH
incr calcitriol
no effect on calcitonin

30

low free calcium concentration are maintained within the ____

cytoplasm

31

calcium is needed in higher concentrations where

in the cells to carry out fxns

32

cell activation by ___, ___ or ___ results in increased calcium entering the cell by diffusion or by the opening of calcium channels

depolarization
neurotransmitters
hormones

33

calcium is a major structural element in ___ and ___

bone and teeth

34

the mineral component of bone consists mainly of___

hydroxyapatite

35

_____ begin remodeling by dissolving or resorbing bone

osteoclats

36

_____ synthesize new bone to replace the bone that was resorbed

osteoblasts

37

during normal growth, bone formation_____ bone resportion

exceeds

38

_______ may result when bone resorption chronically exceeds formation

osteoporosis

39

functions of calcium

bone mineralization
nerve conduction
muscle contraction
coagulation

40

calcium entering the neuron triggers the release of _____ signalling muscle contraction

acetyl choline

41

when mm fiber receives nerve impulse to contract, calcium channels in the cell membrane _____ to allow a small number of calcium ions into the muscle cell

open

42

the binding of calcium is required for the activation of several ______dependent clotting factors in the coagulation cascade

vitamin k

43

most of the calcium in the blood is filtered and reabsorbed by the ____

kidney

44

calcium is primarily excreted from the body in the

urine and feces (also perspiration a bit)

45

Deficiency of calcium results in

hypocalcemia
osteoporosis

46

T or F calcium deficiency is most common in women over the age of 12, and the elderly

true

47

hypocalcemia usually implies____ and is rarely due to low dietary calcim intake

parathyroid function

48

other causes of hypocalcemia

chronic kidney failure
vitamin d deficiency
low blood magnesium
(usually caused by alcoholism)

49

symptoms of hypocalcemia

tetany and muscle spasm, muscle pain ad parashtesias

50

low seruum calcium levels cause what

muscle spasms

51

why does low serum calcium levels cause muscle spasm

because the permeability of neuronal membranes to sodium ions increases, causing a progressive depolarization, which increases the possibility of generating action potentials

52

tests for hypocalcemia

chvosteks sign
trousseaus sign

53

what is chvosteks sign

abnormal spasm of facial muscle elicited by a light taps on the cheek

54

what is trousseaus sign

the wrist and metacarpophalangeal joints flex, the DIP and PIP joints extend and the fingers adduct

55

how do you elicit a trousseaus sign

a blood pressure cuff is placed around the arm and inflated for three minutes. this will occlude the artery and in absence of flow the patients hypocalcemia and neuromuscular irritability will induce spasm

56

what is osteoporosis

increase bone fragility and fracture risk

57

chronically ___ calcium intake may result in a failure to attain optimal bone mass

low

58

once peak bone mass is acheived, inadequate __ intake may contribute to osteoporosis

calcium

59

clinical indications for calcium supplementation

osteoporosis
kidney stones

60

_____resulting from the over consumption of calcium from FOOD has never been reported

hypercalcemia

61

hypercalcemia has been reported with consumption of large quantities of ___-

calcium supplements

62

symptoms of mild hypercalcemia include

loss of appetite
n/v
constipation
abd pain
dry mouth, thirst
freq urination

63

sever hypercalcemia may result in

confusion
delerium
coma
death

64

increase dietary calcium has been associated with a _____ risk of kidney stones

decreased

65

high calcium may decrease the absorption of

non heme iron
zinc

66

high calcium intake may decrease tissue levels of

mg

67

high __ intake can increase calcium excretion in the urine

sodium