Zinc Flashcards
Is zincs availability affected by heat? (aka cooking)
Yes
Who is more likely to be deficient in zinc?
elderly and vegetarians
what protein is stored zinc usually bound to?
thionein as metallothionein
T/F zinc can deactivate reactive oxygen species
True
How does zinc transport from lumen to cell?
ZIP4 transporter
what does ZIP4 stand for?
Zrt and Irt-like protein 4
T/F zinc can passively diffuse into the cell
True
T/F zinc can be absorbed via paracellular absorption with high intake
True
How does zinc transport out of the cell to the plasma?
ZnT1
what does zinc bind to after its transported out of the cell to the plasma?
albumin
which transporter transports zinc from both the cell to lumen and lumen to cell?
ZnT5B
how does zinc transport into cell from the plasma?
ZIP5
T/F regardless of transport, (paracellular, transcellular) zinc will bind to albumin in the plasma
True
which of these enhances absorption of zinc? (multiple answers)
a. Polycyclic acid
b. Citric acid
c. Picolinic acid
d. Glucagon
e. Prostaglandins
f. amino acids (cysteine & histamine)
g. amino acids (lysine & methionine)
h. low zinc status
b,c,e,f,h
T/F cysteine/histamine are good chelators of zinc
True
which of these inhibits absorption of zinc? (multiple answers)
a. phytates
b. phyrates
c. polyphenols
d. sulfuric acid
e. oxalic acid
f. iron, calcium, and copper
g. NSAIDS
h. aspirin
a,c,e,f,h
how do phytates inhibit zinc?
when they bind to zinc they make it non bioavailable
What is the name of the complex where zinc is stored in the cell?
Metallothionein
What is CRIP?
a. an external protein that actively transports zinc into the cell
b. an internal cell protein that moves zinc around via intracellular transport
c. an internal cell protein that intracellularly transports zinc to storage
d. an external protein that binds to zinc making it more polar
b
name three ligands/chelates that bind to zinc in the small intestine
oxalate
phytate
tannin
T/F once a ligand/chelate binds to zinc, it is either transported into the cell by ZIP4 or excreted out
True
Which of these transporters transport zinc in the blood? (multiple answers)
a. transferrin
b. beta-1 metalloglobulin
c. immunoglobulin G
d. alpha-2 macroglobulin
e. zinc hemotransferase
a,c,d
which organ is zinc primarily located in?
liver
which vitamin increases zinc absorption?
a. vitamin B1
b. Vitamin C
c. Vitamin A
d. Vitamin D
c. Vitamin A
Which nutrient decreases zinc absorption?
a. Calcium
b. Potassium
c. Sodium
d. Titanium
a
Does copper decrease zinc absorption?
Yes
How is zinc mainly excreted?
GI tract
What disease is caused by a mutation in ZIP4 which causes poor zinc absorption?
Acrodermatitis enteropathica
How do you treat Acrodermatitis enteropathica? How does this treatment work?
highly toxic doses of zinc: allows zinc to be absorbed via paracellular diffusion
whats the RDA for men/women?
men: 11mg women: 8mg
