Protein

1. What are proteins primarily made of?
A) Lipids
B) Carbohydrates
C) Amino acids
D) Sugars

2. Which of the following elements is NOT found in proteins?
A) Nitrogen
B) Carbon
C) Phosphorus
D) Oxygen

3. What type of bond links amino acids in proteins?
A) Peptide bond
B) Hydrogen bond
C) Ionic bond
D) Covalent bond

4. What percentage of the dry weight of cells is made up of proteins?
A) 50%
B) 25%
C) 75%
D) 10%

5. Which is NOT a source of animal protein?
A) Chicken
B) Wool
C) Fish
D) Eggs

6. What general groups do amino acids contain?
A) Amino and carboxyl
B) Carboxyl and phosphate
C) Hydroxyl and carbonyl
D) Sulfate and amino

7. How many amino acids are essential for humans?
A) 10
B) 20
C) 15
D) 5

8. What is the primary function of proteins in the body?
A) Providing energy
B) Building and repairing tissues
C) Transporting oxygen
D) Storing fat

9. What type of structure do proteins make up in the body?
A) Carbohydrates
B) Non-bony structures
C) Fatty acids
D) Nucleic acids

10. How many amino acids are there in total?
A) 15
B) 20
C) 10
D) 30

11. What is eliminated when two amino acids form a peptide bond?
A) Oxygen molecule
B) Water molecule
C) Nitrogen molecule
D) Carbon molecule

12. Which of the following is an example of a protein source?
A) Rice
B) Eggs
C) Potatoes
D) Apples

13. What is the side chain in an amino acid denoted by?
A) R
B) H
C) O
D) N

14. Which element is always present in amino acids but not in carbohydrates?
A) Hydrogen
B) Nitrogen
C) Carbon
D) Oxygen

15. What is the structure of proteins formed by?
A) Lipids
B) Nucleotides
C) Amino acids
D) Glucose

16. What is the main function of essential amino acids?
A) Stored as fat
B) Synthesized by the body
C) Obtained through diet
D) Converted to glucose

17. What makes up the majority of hair, nails, and feathers?
A) Lipids
B) Proteins
C) Sugars
D) Minerals

18. What is the main role of proteins in muscles?
A) Provide energy
B) Build and repair tissues
C) Store oxygen
D) Generate heat

19. Which of the following is a source of dietary protein?
A) Fruits
B) Meat
C) Oil
D) Sugar

20. What is the simplest unit of a protein?
A) Peptide
B) Carbohydrate
C) Amino acid
D) Fatty acid

21. What happens to proteins during hydrolysis?
A) They are broken down into amino acids
B) They form glucose
C) They convert into lipids
D) They remain unchanged

22. Which type of amino acids must be obtained from food?
A) Non-essential
B) Essential
C) Hydroxyl
D) All amino acids

23. What percentage of dry animal weight is typically made up of proteins?
A) 10%
B) 20%
C) 50%
D) 70%

24. What is the main difference between essential and non-essential amino acids?
A) Non-essential can be synthesized by the body
B) Essential amino acids provide energy
C) Non-essential are more important
D) Essential amino acids are used in enzymes

25. Where are proteins found in large quantities in the body?
A) Bones
B) Muscles
C) Skin
D) Both B and C

26. What role do amino acids play in proteins?
A) They form enzymes
B) They act as building blocks
C) They store energy
D) They help in digestion

27. Which bond is formed between amino acids?
A) Ionic bond
B) Peptide bond
C) Hydrogen bond
D) Covalent bond

28. Which of the following is an example of a protein-rich food?
A) Apples
B) Rice
C) Fish
D) Bread

29. Which functional groups are present in amino acids?
A) Hydroxyl and methyl
B) Carboxyl and amino
C) Sulfate and phosphate
D) Carbonyl and hydroxyl

30. What is the primary building block of proteins?
A) Glucose
B) Amino acids
C) Lipids
D) Nucleotides

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Correct Answers:

1. C
2. C
3. A
4. A
5. B
6. A
7. A
8. B
9. B
10. B
11. B
12. B
13. A
14. B
15. C
16. C
17. B
18. B
19. B
20. C
21. A
22. B
23. C
24. A
25. D
26. B
27. B
28. C
29. B
30. B