Phosphorous

Question 1

How is phosphorous digested and absorbed

Answer 1

both active and passive (60-70%)

Question 2

How is phosphorus exreted

Answer 2

feces (unabsorbed and endogenous P) and urine (inorganic)

Question 3

Metabolic roles of phosphorus

Answer 3

1)calcification of bone
2)formation of dentin
3)intracellular buffer
4)phosphorus containing organic cpds (ATP, DNA, TPP, NADP, FAD, PLP)
5)cell membrane structure
6)energy metabolism

Question 4

Hypophosphatemia

Answer 4

genetic deficiency disease
Risk population: pre-mature infants, antacid users

Question 5

What systems does hypophosphatemia affect

Answer 5

bones/teeth, cellular energy metabolism, acid/base balance

Question 6

Signs of deficiency

Answer 6

impaired skeletal mineralization, bone pain, increased hemolysis of RBCs, muscle weakness, impaired renal function

Question 7

DRI/RDA

Answer 7

700mg/day

Question 8

UL

Answer 8

4000 mg/day

Question 9

Food sources

Answer 9

found in most food; dairy, meat, and fish high sources

Question 10

Toxicity

Answer 10

Hyperphosphatemia (if renal function is impaired)

Question 11

Renal osteodystrophy

Answer 11

high serum P triggers PTH secretion to increase bone reabsorption