Question 1

Which of the following dietary components impedes copper absorption?

Accepted Answer

Phytic acid, found in grains and legumes, can bind to copper and inhibit its absorption.

Question 2

Which trace mineral participates in the greatest number of enzyme systems?

Accepted Answer

Zinc is involved in the function of over 300 enzymes and plays a vital role in numerous biological processes, more than any other trace mineral.

Question 3

Excessive intake of non-heme iron interferes with absorption of which mineral by an unknown mechanism?

Accepted Answer

Excessive intake of non-heme iron can interfere with the absorption of zinc by an unknown mechanism. This is why it is important to balance intake of both minerals for optimal absorption and utilization in the body.

Question 4

Which of the microminerals is considered essential for normal brain function?

Accepted Answer

Manganese is considered essential for normal brain function as it helps with neurotransmitter activity and the synthesis of fatty acids that are important for brain health. Chromium and vanadium are important for glucose metabolism and insulin regulation, while fluorine is not considered an essential micronutrient for humans.

Question 5

Absorption of dietary iron is regulated by _____, produced by the liver when iron stores are high and released to the blood to act at the surface of enterocytes and macrophages.

Accepted Answer

Hepcidin is a hormone produced by the liver that regulates iron absorption and distribution in the body. It is released when iron stores are high and acts to decrease iron absorption by binding to ferroportin on enterocytes and macrophages, leading to its degradation.

Question 6

ZIP4

Accepted Answer

ZIP4 is a zinc transporter that is primarily expressed in the enterocytes of the small intestine, where it transports dietary zinc into the body. Mutations in ZIP4 can cause acrodermatitis enteropathica, a rare inherited disorder that can lead to zinc deficiency and its associated symptoms. ZIP4 expression is not limited to the liver, and its degradation is not dependent on zinc intake.

Question 7

At the cellular level, which mineral interacts with vitamin A by promoting growth and helping to synthesize retinol-binding protein?

Accepted Answer

Zinc interacts with vitamin A by promoting growth and helping to synthesize retinol-binding protein.

Question 8

In the presence of low intracellular iron, the binding of iron regulatory protein (IRE-BP) to iron response elements (IRE) present on the ferritin mRNA:

Accepted Answer

When intracellular iron is low, IRE-BP binds to IREs on ferritin mRNA, blocking its translation and thus decreasing ferritin abundance.

Question 9

Hemoglobin and hematocrit are common measurements for assessment of nutriture for which mineral?

Accepted Answer

Hemoglobin and hematocrit are measurements used to assess iron levels in the body. Iron is essential for the production of hemoglobin, the protein in red blood cells that carries oxygen throughout the body. Hematocrit measures the proportion of red blood cells in the blood, which is also affected by iron levels. Therefore, the correct answer is D) iron.

Question 10

Iron content of the average Western diet is estimated to be about

Accepted Answer

The answer of Iron content of the average Western diet...

Question 11

The following vitamins/ minerals are required for heme synthesis:

Accepted Answer

Vitamin B6, zinc, and iron are essential for heme synthesis. Vitamin B6 is a cofactor for the enzyme ALA synthase, zinc is involved in the regulation of heme synthesis, and iron is a core component of the heme molecule.

Question 12

The binding of iron by proteins defends the cells against

Accepted Answer

Binding of iron by proteins protects cells from oxidative damage caused by free radicals, which can damage cellular structures and lead to various diseases. Iron deposition in kidneys and other organs would not be prevented by protein binding, and tissue hypoxia and stellate cells are not related to iron binding.

Question 13

Zinc is important for taste perception as a component of _____.

Accepted Answer

Zinc is a component of gustin, a salivary protein that is important for taste perception.

Question 14

The enzyme that converts retinol to retinal and ethanol to acetyl-aldehyde contains 4 ____ atoms.

Accepted Answer

The enzyme that catalyzes the conversion of retinol to retinal and ethanol to acetyl-aldehyde is alcohol dehydrogenase, which contains zinc atoms.

Question 15

Which statement is false?

Accepted Answer

The answer of Which statement is false?
...

Question 16

Which vitamin may enhance copper reduction?

Accepted Answer

Ascorbic acid (Vitamin C) can enhance copper reduction by acting as a reducing agent.

Question 17

Where would you find iron regulatory element binding protein (IRE-BP)?

Accepted Answer

IRE-BP is found in the cytosol where it regulates iron metabolism by binding to iron-responsive elements on mRNA.

Question 18

Which of the following dietary substances inhibits uptake of non-heme iron?

Accepted Answer

Tea contains tannins, which can bind to non-heme iron and inhibit its absorption. Ascorbic acid (vitamin C) can actually enhance the uptake of non-heme iron. Lactic acid does not have a significant impact on iron absorption. MFP (meat, fish, and poultry) can enhance the absorption of non-heme iron, but this question is asking for a dietary substance that inhibits uptake.

Question 19

Which mineral facilitates transfer of electrons in the electron transport chain?

Accepted Answer

Iron facilitates transfer of electrons in the electron transport chain.

Question 20

Which mineral is critical for oxidizing iron to be bound by transferrin for delivery to the tissues from the gut and liver?

Accepted Answer

Copper is critical for oxidizing iron so that it can be bound by transferrin for delivery to the tissues from the gut and liver.

Quiz 13: Essential Trace and Ultratrace Minerals