Questions and Answers
Which of the microminerals is considered essential for normal brain function?
manganese
Iron content of the average Western diet is estimated to be about?
5 to 7 mg iron per 1,000 kcal
Which of the following dietary substances inhibits uptake of non-heme iron?
tea
Absorption of dietary iron is regulated by _____, produced by the liver when iron stores are high.
Signup and view all the answers
Which mineral is critical for oxidizing iron to be bound by transferrin for delivery to the tissues?
Signup and view all the answers
Where would you find iron regulatory element binding protein (IRE-BP)?
Signup and view all the answers
In the presence of low intracellular iron, what happens to ferritin mRNA?
Signup and view all the answers
The binding of iron by proteins defends the cells against?
Signup and view all the answers
Hemosiderin is the primary storage form of iron in cells.
Signup and view all the answers
The following vitamins/minerals are required for heme synthesis.
Signup and view all the answers
Which mineral facilitates transfer of electrons in the electron transport chain?
Signup and view all the answers
Excessive intake of non-heme iron interferes with absorption of which mineral?
Signup and view all the answers
Hemoglobin and hematocrit are common measurements for assessment of nutriture for which mineral?
Signup and view all the answers
ZIP4 is what?
Signup and view all the answers
Which trace mineral participates in the greatest number of enzyme systems?
Signup and view all the answers
The enzyme that converts retinol to retinal and ethanol to acetyl-aldehyde contains 4 ____ atoms.
Signup and view all the answers
Zinc is important for taste perception as a component of _____.
Signup and view all the answers
At the cellular level, which mineral interacts with vitamin A by promoting growth?
Signup and view all the answers
Which vitamin may enhance copper reduction?
Signup and view all the answers
Which of the following dietary components impedes copper absorption?
Signup and view all the answers
The protein that plays a dual function in both iron and copper homeostasis is:
Signup and view all the answers
What glycoprotein serves as a transporter of copper, an antioxidant, and an oxidative enzyme?
Signup and view all the answers
What two minerals can cause damage to cells when in their free ion forms?
Signup and view all the answers
What genetic disorder causes copper toxicity?
Signup and view all the answers
Free selenide can be converted into selenophosphate.
Signup and view all the answers
Which mineral is an essential factor in the action of glutathione peroxidase in the reduction of organic peroxides?
Signup and view all the answers
When superoxide radicals accumulate, what happens to hydrogen peroxide?
Signup and view all the answers
Glutathione loses two electrons when it acts as an antioxidant. Glutathione is _____.
Signup and view all the answers
What is important in antioxidant DEFENSE?
Signup and view all the answers
Which micromineral is necessary for iodine metabolism?
Signup and view all the answers
Which non-metal nutrient deficiency is associated with Keshan disease?
Signup and view all the answers
Chromium absorption is inhibited by _____ and enhanced by _____.
Signup and view all the answers
Which mineral is thought to potentiate the action of insulin?
Signup and view all the answers
The primary physiological role of which mineral is as a constituent in the thyroid hormones?
Signup and view all the answers
Study Notes
Microminerals and Their Functions
- Manganese is essential for normal brain function.
- Average iron intake in the Western diet ranges from 5 to 7 mg per 1,000 kcal.
- Tea inhibits the absorption of non-heme iron.
- Hepcidin regulates dietary iron absorption; produced by the liver in response to high iron stores.
- Copper is necessary for oxidizing iron to allow binding by transferrin for tissue delivery.
Iron Regulation and Storage
- Iron regulatory element binding protein (IRE-BP) is located in the cytosol.
- Low intracellular iron causes IRE-BP to bind to iron response elements, decreasing ferritin abundance.
- Iron-binding proteins protect cells from oxidative damage caused by free radicals.
- Hemosiderin is not the primary storage form of iron; ferritin is the main storage protein.
- Important nutrients for heme synthesis include vitamin B6, zinc, and iron.
Zinc and Its Roles
- Iron facilitates electron transfer in the electron transport chain.
- Excessive non-heme iron intake can hinder zinc absorption.
- Hemoglobin and hematocrit levels are crucial for monitoring iron status.
- ZIP4 is the main transporter for zinc into enterocytes.
- Zinc plays a significant role in numerous enzyme systems and is key for taste perception through its component, gustin.
Zinc's Interaction and Functions
- Zinc aids in the growth of cells and synthesis of retinol-binding protein, influencing vitamin A.
- Ascorbic acid may enhance copper reduction.
- Phytic acid impedes copper absorption.
- Ceruloplasmin is critical for both iron and copper homeostasis, functioning as a transporter and antioxidant.
Selenium and Antioxidant Defense
- Iron and copper in free ion forms can be harmful to cells.
- Menkes disease is a genetic disorder that leads to copper toxicity.
- Free selenide in selenium metabolism can convert into selenophosphate.
- Selenium is a vital component of glutathione peroxidase, reducing organic peroxides and hydrogen peroxide.
- Superoxide dismutase facilitates the conversion of superoxide radicals into hydrogen peroxide, which is then turned into water and oxygen by catalase or glutathione peroxidase.
Additional Microminerals
- Glutathione is oxidized as it acts as an antioxidant, losing two electrons.
- Both selenium and chromium play roles in antioxidant defense and metabolism.
- Selenium is necessary for proper iodine metabolism and is linked to Keshan disease, which presents as cardiomyopathy.
- Chromium's absorption can be inhibited by antacids and enhanced by picolinate; it is believed to enhance insulin action.
- Iodine is a crucial component of thyroid hormones, underlining its physiological importance.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge with these flashcards from Nutrition Chapter 13. Explore essential microminerals, iron content in diets, and factors affecting iron absorption. Perfect for students aiming to master the concepts in nutrition science.
