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.
Last updated
1,790 questions · page 45 of 90
- A. Position 01 of pentose sugar
- B. Position 05 of pentose sugar
- C. Position 03 of pentose sugar
- D. Position 02 of pentose sugar
Explanation: In nucleotides, the nitrogenous base is always attached to the 1' carbon of the pentose sugar.
Correct answer: Position 01 of pentose sugar- A. Nucleoside
- B. Nucleotide
- C. Nucleic acid
- D. Nuclein
Explanation: The correct answer is nucleoside. A nucleoside is formed when a nitrogenous base combines with a pentose sugar.
Correct answer: Nucleoside- A. FAD
- B. NAD
- C. ATP
- D. AMP
Explanation: Adenosine triphosphate (ATP) is the correct answer because it is universally recognized as the primary energy currency of the cell.
Correct answer: ATP- A. DNA
- B. RNA
- C. ATP
- D. AMP
Explanation: DNA is the correct answer because it contains the genetic blueprint that determines the properties and potential activities of a cell.
Correct answer: DNA- A. RNA
- B. DNA
- C. Proteins
- D. ATP (Adenosine Triphosphate)
Explanation: DNA is the correct answer because it is the primary hereditary material responsible for storing and transmitting genetic information in…
Correct answer: DNA- A. Three
- B. Four
- C. Five
- D. Six
Explanation: DNA is made up of four different types of nucleotides: adenine (A), thymine (T), cytosine (C), and guanine (G).
Correct answer: Four- A. ATP
- B. ADP
- C. GTP
- D. NAD
Explanation: The correct answer is NAD. Nicotinamide adenine dinucleotide (NAD) is a dinucleotide, which means it is composed of two nucleotide units.
Correct answer: NAD- A. Deoxyribonucleotide
- B. Deoxyribonucleoside
- C. Ribonucleotide
- D. Ribonucleoside
Explanation: The question describes a combination of ribose, a nitrogenous base, and phosphoric acid.
Correct answer: Ribonucleotide- A. AMP, ADP, ATP
- B. UMP, UDP, UTP
- C. CMP, CDP, CTP
- D. TMP, TDP, TTP
Explanation: Option B is correct because UMP, UDP, and UTP are ribonucleotides that contain uracil and ribose sugar, not the deoxyribose sugar…
Correct answer: UMP, UDP, UTP- A. Adenosine, Guanosine, Cytidine, Thymidine
- B. Adenosine, Guanosine, Thymidine, Uridine
- C. Adenosine, Uridine, Thymidine, Cytidine
- D. Uridine, Guanosine, Thymidine, Cytidine
Explanation: The correct nucleosides of DNA are Adenosine, Guanosine, Cytidine, and Thymidine.
Correct answer: Adenosine, Guanosine, Cytidine, Thymidine- A. Maurice Wilkins
- B. Erwin Chargaff
- C. Watson and Crick
- D. Rosalind Franklin
Explanation: Erwin Chargaff was instrumental in uncovering the ratios of nucleotide bases in DNA, leading to Chargaff's rules: the amount of adenine…
Correct answer: Erwin Chargaff- A. Adenine and Guanine are equal
- B. Guanine and thymine are equal
- C. Adenine and cytosine are equal
- D. Adenine and thymine are equal and so are cytosine and guanine
Explanation: Chargaff's rules are fundamental to understanding DNA structure. His data showed that in DNA, the amount of adenine (A) is equal to the…
Correct answer: Adenine and thymine are equal and so are cytosine and guanine- A. James D. Watson and Francis Crick
- B. Maurice Wilkins and Rosalind Franklin
- C. P.A Leneve and T.H Morgan
- D. None of these
Explanation: The correct answer is James D. Watson and Francis Crick, who built the first accurate scale model of DNA with significant contributions…
Correct answer: James D. Watson and Francis Crick- A. Protein
- B. Lipid
- C. Vitamin
- D. Water
Explanation: The correct answer is Water. Water acts as a fluid cushion around organs, providing protection against trauma by absorbing shocks and…
Correct answer: Water- A. Polarity
- B. Universal solvent
- C. High specific heat and High heat of vaporization
- D. Polarity, Universal solvent, High specific heat and High heat of vaporization
Explanation: Water is biologically important due to its unique properties. The correct answer is Polarity, Universal solvent, High specific heat and…
Correct answer: Polarity, Universal solvent, High specific heat and High heat of vaporization- A. 20%
- B. 10%
- C. 70%
- D. 50%
Explanation: Water is vital for the survival of cells as it facilitates biochemical reactions, aids in transportation within the cell, and helps…
Correct answer: 70%897. It is a process in which large organic molecules are synthesized and water molecule is removed:
- A. Hydrolysis
- B. Condensation
- C. Hydrogenation
- D. Decarboxylation
Explanation: The correct answer is Condensation. In condensation reactions, smaller molecules combine to form larger organic molecules, and a water…
Correct answer: Condensation- A. Hydrophobic properties
- B. Hydrophilic properties
- C. Very good solvent
- D. Strong surface tension
Explanation: Hydrophobic properties refer to the tendency of certain substances to repel or not mix well with water.
Correct answer: Hydrophobic properties899. Polysaccharides are:
- A. Insoluble in hot water
- B. Sparingly soluble in hot water
- C. Sparingly soluble in cold water
- D. Highly soluble in hot water
Explanation: Polysaccharides, composed of long chains of monosaccharide units, exhibit limited solubility in hot water due to their complex molecular…
Correct answer: Sparingly soluble in hot water- A. Liver
- B. Spleen
- C. White Blood Cells (W.B.C.)
- D. Skin cells
Explanation: The correct answer is the liver. The liver is responsible for storing glycogen, which is a form of glucose storage.
Correct answer: Liver