Which of the following is true regarding iron absorption? a. ...

[mmm]

Which of the following is true regarding iron absorption?
 
  a. Vegetable nonheme iron is more easily absorbed than heme iron.
  b. Most of the iron consumed is absorbed.
  c. Ascorbic acid (vitamin C) enhances absorption.
  d. Those who are iron deficient absorb less iron.

Question 2

What is the mechanism for iron toxicity if iron is present in excess amounts?
 
  a. Acts as a catalyst in forming free oxygen radicals
  b. Impedes hematopoiesis
  c. Reduces hemoglobin to methemoglobin
  d. Interferes with globin synthesis

[bobsmith]

Answer to Question 1

ANS: C
Ascorbic acid (vitamin C) does enhance absorption of iron. Vegetable nonheme iron is less readily absorbed than heme iron, even though it makes up more of our dietary iron source. Only approximately 10 of dietary iron is absorbed per day. People who are iron deficient absorb a larger percent of iron than do normal persons.

Answer to Question 2

ANS: A
Iron has reduction (redox) potential, and easily cycles between ferrous (reduced) and ferric (oxidized) forms. If it is found in excess, then it plays a key role in forming harmful oxygen radicals that can damage cellular structures, thus harming cells in the process.

[mmm]

Correct answers!

[bobsmith]

Great! Please up vote