Free Biological Molecules MCQs with Answers
1,790 Biological Molecules MCQs from Biology, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
The chapter covers water's polarity and biological roles, carbohydrates, lipids, proteins and nucleic acids, including their monomers, bonds, structures and functions. It also distinguishes RNA from DNA and explains conjugated molecules such as glycoproteins, glycolipids and nucleoproteins, which combine organic molecules with a non-protein component.
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1,790 questions · page 23 of 90
- A. 10
- B. 2
- C. 34
- D. 54
Explanation: The two strands of DNA are wound around each other so that there are 10 base pairs in each turn of the helix.
Correct answer: 10- A. Primary Structure
- B. Secondary Structure
- C. Quatemary Structure
- D. Tertiary Structure
Explanation: Globular structure of enzyme has a very important role in its activity and this globular structure attains at least tertiary level…
Correct answer: Tertiary Structure- A. Lipids
- B. Proteins
- C. Polynucleotides
- D. Carbohydrates
Explanation: Carbohydrates are polyhydroxy aldehydes or ketones or complex substances which on hydrolysis yield polyhydroxy aldehyde or ketone…
Correct answer: Carbohydrates- A. Trypsin
- B. Keratin
- C. Insulin
- D. Glucagon
Explanation: Keratin is a fibrous protein having secondary structure and mostly found in nails and hairs.
Correct answer: Keratin- A. Muscle and Liver
- B. Around Thighs and Belly
- C. Around Belly and Hips
- D. Liver and Kidneys
Explanation: Glycogen is called animal starch and it is abundantly found in muscle and liver cells of animal tissue.
Correct answer: Muscle and Liver- A. 170
- B. 20
- C. 25
- D. 45
Explanation: About 170 types of amino acids have been found to occur in cells and tissues. Of these, about 25 are constituents of proteins.
Correct answer: 170- A. 20
- B. 170
- C. 25
- D. 200
Explanation: There are 20 standard amino acids that are commonly found in cells and tissues.
Correct answer: 20- A. Oils
- B. Waxes
- C. Phenols
- D. Fats
Explanation: Fats containing unsaturated fatty acids are usually liquid at room temperature and are said to be oils.
Correct answer: Oils- A. 2nm
- B. 3.4nm
- C. 34nm
- D. 4nm
Explanation: The two strands of DNA are wound around each other so that there are 10 base pairs in each turn of about 3.4nm.
Correct answer: 3.4nm- A. Monosaccharide
- B. Disaccharides
- C. Oligosaccharides
- D. Polysaccharides
Explanation: Polysaccharides are made up of many monosaccharides subunits and have higher molecular weight as compared to monosaccharides and…
Correct answer: Polysaccharides- A. Hydrogen bond
- B. Amino group
- C. R-group
- D. Disulphide bond
Explanation: The a-helix is a very uniform geometric structure with 3.6 amino acids in each turn of the helix.
Correct answer: Hydrogen bond452. The number and sequence of amino acids along a polypeptide chain is called _ structure of a protein.
- A. Secondary
- B. Quaternary
- C. Primary
- D. Tertiary
Explanation: The primary structure of a protein is described by number, sequence and type of amino acids in a polypeptide chains.
Correct answer: Primary- A. With the release of large amount of water vapors, a small amount of heat loss can take place
- B. No cooling effect with the release of even large amount of water vapors
- C. It will keep their temperature very high
- D. With the release of small amount of water vapors, a great amount of heat loss can take place
Explanation: Water absorbs much heat as it changes from liquid to gas and causes a cooling effect.
Correct answer: With the release of small amount of water vapors, a great amount of heat loss can take place- A. Glucose
- B. Glycogen
- C. Galactose
- D. Glucagon
Explanation: Glycogen is animal starch found in liver and muscle cell while starch is stored in plants cells.
Correct answer: Glycogen- A. Carboxyl bond
- B. Hydroxyl bond
- C. Hydrogen bond
- D. Glycosidic bond
Explanation: When two monosaccharides join through dehydration condensation process they form disaccharide with glycosidic linkage and release water…
Correct answer: Glycosidic bond- A. 16 types of Amino acids
- B. 10 types of Amino acids
- C. 170 types of Amino acids
- D. 20 types of Amino acids
Explanation: About 170 types of amino acids have been found to occur in cells and tissues. Of these about 25 are constituents of proteins.
Correct answer: 20 types of Amino acids457. In glycine R is _.
- A. Fatty acid
- B. Ethane
- C. Hydrogen
- D. Methane
Explanation: Amino acids Fibrous mainly differ due to the type or nature of R group.
Correct answer: Hydrogen- A. Lower proportion of C-H bonds
- B. Higher proportion of C-H bonds
- C. Higher proportion of C-O bonds
- D. Glycerol and sulfuric acid
Explanation: C-H bond is a potential source of energy. Lipids have a higher proportion of C-H bonds as compared to carbohydrates and proteins.
Correct answer: Higher proportion of C-H bonds- A. Adenosine
- B. ATP
- C. Guanine
- D. NAD
Explanation: Adenosine is a nucleoside while guanine is a nitrogenous base. NAD is a dinucleotide. Only ATP is a nucleotide among all options.
Correct answer: ATP- A. Thermoregulation
- B. Osmoregulation
- C. Metabolism
- D. Isomerism
Explanation: Word metabolism is derived from Greek word which means "Changes". Temperature regulation, water and salt regulation respectively called…
Correct answer: Metabolism