Micronutrients: Trace Elements Flashcards
Eleven elements account for ______ percent of body weight.
99.7
The most critical period of brain development is _______________.
the first 1,000 days
The body contains about ______ grams of iron.
5
Where is most of the iron in the body?
In hemoglobin (50%)
Other than hemoglobin, what enzymes contain iron?
Oxygenases and cytochromes
Iron is better absorbed in the _________ state.
heme
What molecule in spinach leads to negative absorption of iron?
Phyate, a carbon ring with many phosphates that can chelate cations
When hepcidin is increased, ____________ is inhibited.
export of iron from iron-storing cells
What stimulates the release of hepcidin?
Inflammation; it serves to sequester iron in cells, thereby hiding it from bacteria
The most common micronutrient deficiency in the world (including the U.S.) is _____________.
iron deficiency
The neurologic effects of iron deficiency are _____________, even with correction.
irreversible
Zinc is important for _______________.
any kind of growth or differentiation: immune cells, wound healing, GI tract integrity, and skin renewal
Breastmilk concentrations of zinc do not correlate with __________.
maternal zinc levels
____________ is non-toxic, so it’s ok that some people take lozenges of this when they’re sick.
Zinc
Breastmilk levels of zinc are low are ________ months.
six
________ deficiency can make children not want to eat.
Zinc
Micronutrients are those that we need less than __________ of per day.
100 mg
How does vitamin C promote iron absorption?
It converts Fe3+ to Fe2+, which is the form in which iron is absorbed.
Deficiencies of iron in which two populations warrants investigation for unseen bleeding?
Men and post-menopausal women
Again, what lab value can help you differentiate between inflammatory and iron-deficient anemia?
High ferritin indicates inflammatory anemia, while low ferritin indicates iron-deficiency anemia.
List three cellular roles of zinc.
- Part of transcription factor in zinc-finger domains
- Part of metalloproteases
- Increases membrane stability
True or false: zinc, unlike iron, can be excreted in the GI tract.
True.
What category of enzymes require copper: ______________.
oxidases
Severe __________ deficiency can lead to hypothyroidism.
iodide
Why does milk decrease iron absorption?
Because calcium decreases iron absorption
Hepcidin acts by _____________.
inhibiting ferroportin, thereby causing iron to accumulate in cells
Inability to develop secondary sexual characteristics is a feature of ______________ deficiency.
zinc
Stunting is strongly associated with _____________ deficiency.
zinc
Currently, there is no reliable marker for ____________ deficiency.
zinc
