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Ascorbic Acid (Vitamin C)
Nutrition
This document provides a comprehensive overview of ascorbic acid (Vitamin C), covering its forms, measurement, functions, utilization, malnutrition signs, toxicity, recommended allowances, and food sources. It details how Vitamin C is essential for various bodily functions, its susceptibility to degradation, absorption, and excretion, and the consequences of its deficiency.
Vitamins
Health
Biochemistry
30 Questions
Easy
Ages 12+
Mar 23, 2026
About this Study Set
This study set covers Nutrition through
30 practice questions.
This document provides a comprehensive overview of ascorbic acid (Vitamin C), covering its forms, measurement, functions, utilization, malnutrition signs, toxicity, recommended allowances, and food sources. It details how Vitamin C is essential for various bodily functions, its susceptibility to degradation, absorption, and excretion, and the consequences of its deficiency. Every question includes the correct answer so you can learn as you go — pick any format above to get started.
Questions & Answers
Browse all 30 questions from the
Ascorbic Acid (Vitamin C) study set below.
Each question shows the correct answer — select a study format above to practice interactively.
1
What is another name for Vitamin C, and why is it called that?
-
A
Ascorbic acid, because it is an antioxidant
-
B
Antiscorbutic vitamin, because it prevents scurvy
-
C
Citric acid, because it is found in citrus fruits
-
D
L-ascorbic acid, because it is the most active form
2
Which of the following are the most active forms of Vitamin C?
-
A
L-ascorbic acid and diketogulonic acid
-
B
L-dehydroascorbic acid and diketogulonic acid
-
C
L-ascorbic acid and L-dehydroascorbic acid
-
D
D-ascorbic acid and L-ascorbic acid
3
What is the unit of measurement for Vitamin C?
-
A
Milligrams (mgs)
-
B
Micrograms (mcgs)
-
C
Grams (gs)
-
D
International Units (IUs)
4
Vitamin C is crucial for the formation and maintenance of what substance that holds cells together?
-
A
Cellular fluid
-
B
Intercellular cementing substance
-
C
Mitochondria
-
D
Ribosomes
5
Which of these bodily structures' integrity is NOT explicitly mentioned as being maintained by ascorbic acid?
-
A
Capillary walls
-
B
Bone marrow
-
C
Nerve cells
-
D
Teeth
6
Vitamin C is necessary for the conversion of folic acid to its active form, known as:
-
A
Folinic acid
-
B
Megaloblastic acid
-
C
Pteroylglutamic acid
-
D
Diketogulonic acid
7
What type of anemia is prevented by Vitamin C?
-
A
Iron deficiency anemia
-
B
Megaloblastic anemia
-
C
Hemolytic anemia
-
D
Sickle cell anemia
8
How does Vitamin C improve iron utilization?
-
A
By converting iron to a more absorbable form
-
B
By making iron more available for hemoglobin formation
-
C
By preventing iron loss from the body
-
D
By increasing the production of iron in the body
9
Vitamin C acts as an antioxidant by protecting normal cells from the damage of:
-
A
Excess glucose
-
B
Free radicals
-
C
High temperatures
-
D
Alkali substances
10
Which of these factors does NOT easily destroy Vitamin C?
-
A
Heat
-
B
Acid
-
C
Light
-
D
Cold
11
In the presence of which two metals is the destruction of Vitamin C hastened?
-
A
Iron and copper
-
B
Zinc and magnesium
-
C
Calcium and potassium
-
D
Sodium and chloride
12
Where is Vitamin C almost completely absorbed in the body?
-
A
Stomach
-
B
Large intestine
-
C
Small intestine
-
D
Esophagus
13
In cases of achlorhydria or gastrointestinal disorders, the absorption of Vitamin C may be affected. What is achlorhydria?
-
A
Excess stomach acid
-
B
Lack of HCl in the stomach
-
C
High levels of bile
-
D
Poor enzyme activity
14
Since there is hardly any storage of Vitamin C in tissues, what is used as an index of vitamin C saturation?
-
A
Adrenal glands
-
B
White blood cells
-
C
Liver
-
D
Plasma
15
Which of these species, along with humans, cannot synthesize Vitamin C from glucose?
-
A
Dogs and cats
-
B
Rats and mice
-
C
Guinea pigs and monkeys
-
D
Cows and sheep
16
What is the enzyme that converts L-gulonic acid to L-ascorbic acid, which is lacking in humans?
-
A
Oxidase
-
B
Catalase
-
C
Peroxidase
-
D
Dehydrogenase
17
What is D-ascorbic acid to L-ascorbic acid?
-
A
A precursor
-
B
A byproduct
-
C
A vitamin antagonist
-
D
An isomer
18
Which of the following is NOT a deficiency sign of Vitamin C at an early stage?
-
A
Irritability
-
B
Weakness
-
C
Swollen gums
-
D
Lack of appetite
19
In severe deficiencies of Vitamin C, what is the deficiency disease called?
-
A
Pellagra
-
B
Rickets
-
C
Scurvy
-
D
Beriberi
20
Which of these is a characteristic symptom of scurvy?
-
A
Night blindness
-
B
Bone deformities
-
C
Bleeding gums
-
D
Dry skin
21
In infantile scurvy, why does the infant flex his legs for comfort, resulting in the "frog's position"?
-
A
Due to swollen thighs and painful joints
-
B
Due to muscle spasms
-
C
Due to fever
-
D
Due to abdominal pain
22
Toxicity cases of Vitamin C (hypervitaminosis C) are rare because:
-
A
It is stored in high amounts in the body
-
B
Excess Vitamin C is easily excreted
-
C
The body develops a tolerance to high doses
-
D
It is not absorbed in large quantities
23
Megadoses of Vitamin C may cause adverse effects in susceptible individuals, such as:
-
A
Improved vision
-
B
Strengthened bones
-
C
Rashes and diarrhea
-
D
Increased energy levels
24
Who generally needs more Vitamin C than females?
-
A
Children
-
B
Older persons
-
C
Males
-
D
Smokers
25
Vitamin C needs are increased during which life stages or conditions?
-
A
Adulthood and old age
-
B
Growth, pregnancy, and lactation
-
C
Sedentary lifestyle
-
D
Low-stress environments
26
According to the Philippine RNI, what is the recommended daily allowance of Vitamin C for adult males (19 years and over)?
-
A
70 mg/day
-
B
75 mg/day
-
C
105 mg/day
-
D
120 mg/day
27
What is the tolerable upper intake level for Vitamin C per day for adults, as stated by US-DRI?
-
A
1,000 mg/day
-
B
1,500 mg/day
-
C
2,000 mg/day
-
D
2,500 mg/day
28
Which of these is considered the richest source of Vitamin C?
-
A
Guava
-
B
Papaya
-
C
Puerto Rico cherry (acerola)
-
D
Orange
29
Which of the following local fruits in the Philippines is NOT listed as an excellent source of Vitamin C?
-
A
Guava
-
B
Mango
-
C
Durian
-
D
Bayabas (guava)
30
Vitamin C is most easily destroyed by heat, oxidation, and:
-
A
Cold
-
B
Sunlight
-
C
Alkali
-
D
Acid
