nutrition
Which of the following is a feature of vitamin D synthesis?
Dark-skinned people require longer sunlight exposure than light-skinned people to synthesize equivalent amounts of vitamin D
Which of the following is a property of the fat-soluble vitamins?
Deficiency symptoms may take years to develop on a poor diet
Which of the following is a property of the tocopherols?
Easily destroyed by air and oxygen
What is the role of vitamin E in the metabolism of free radicals?
Eliminator
Which of the following can the body use to synthesize vitamin D?
Exposure to sunlight
Which of the following is a feature of Accutane?
It is known to cause birth defects when used by pregnant women
Which of the following is a feature of vitamin K?
It participates in synthesis of bone proteins
How is vitamin E thought to play a role in reducing the risk of heart disease?
It slows oxidation of low-density lipoproteins
Which of the following vitamins is synthesized by intestinal bacteria?
K
Which of the following functions of vitamin A accounts for most of the body's need for the vitamin?
Maintaining mucous membranes
Which of the following enables much of the world's population to maintain adequate vitamin D status?
Outdoor exposure of the skin to sunlight
What is/are the main function(s) of vitamin D?
Promotes calcium and phosphorus absorption and promotes calcium mobilization from bone
Which of the following is responsible for transporting vitamin A from the liver to other tissues?
Retinol-binding protein
All of the following are forms of vitamin A except:
Retinoquinone
If a normal, healthy adult were to begin consuming a vitamin A poor diet, approximately how much time would pass before the first deficiency symptoms would appear?
1-2 years
What is the Adequate Intake (AI) level for vitamin D in individuals around 20 years of age?
5 micrograms
What is the adult AI for vitamin K?
90-120 micrograms
What is a free radical?
A molecule that is unstable and highly reactive because it contains unpaired electrons
What is prothrombin?
A protein needed for blood clot formation
What population group is at highest risk for osteomalacia?
Adult women
Which of the following properties do vitamin D and K share?
Both are synthesized in the body
Which of the following features do vitamins C and E share?
Both function as antioxidants
What type of foods should be controlled in individuals taking anticoagulant?
green leafy vegetables
What tissue contains the majority of the body's store of vitamin A?
liver
In what tissues must a molecule of vitamin D be chemically altered to yield a compound that is fully active?
liver and kidney
The effects of vitamin A deficiency are most severe in what population group?
newborns
What population group has the highest risk for vitamin K deficiency?
newborns
Vitamin A supplements are helpful in treating which of the following conditions?
night blindness
What is the name of the vitamin D deficiency disease in adults?
osteomalacia
All of the following are characteristics of excess consumption of beta-carotene except:
overconsumption from supplements is harmless
All of the following are good sources of vitamin A except:
pears
Which of the following is the name of the vitamin A compound that is active in the visual response?
retinal
Which of the following is the most likely side effect for a person who regularly consumes large quantities of carrots or carrot juice?
skin yellowing
Which of the following is most likely to occur from a prolonged dietary deficiency of vitamin A?
xerophthalmia
All of the following are characteristics of vitamin D nutrition except:
the requirement is increased in most people who are exposed to the sun
What is the reason that vitamin E deficiencies are rarely observed in human beings?
The vitamin is widespread in foods
Which of the following is not among the features of the fat-soluble vitamins?
Transported permanently to the liver and adipose tissue
Keratinization of lung cells has been reported in smokers taking high-dose supplements of:
Vitamin A
Which of the following compounds is known to function as a hormone?
Vitamin D
Of the following, which would most readily induce a vitamin K deficiency?
antibiotic therapy
The main function of vitamin E in the body is to act as a(n):
antioxidant
Which of the following substances is converted to vitamin A in the body?
beta-carotene
As far as is known, vitamin A does not play an important role in which of the following processes?
blood clotting
In what chief capacity does vitamin K function?
blood clotting
Which of the following symptoms would indicate a vitamin D deficiency?
bowed legs
Which of the following compounds serves as the major precursor for the body's synthesis of vitamin D?
cholesterol
Which of the following are major sources of vitamin E in the diet?
vegetable oils
Increasing the amount of polyunsaturated fats in the diet increases the need for vitamin
Vitamin E
The process of bone remodeling is known to be dependent on all of the fat-soluble vitamins except:
Vitamin E
Which vitamin is routinely given as a single dose to newborns?
Vitamin K