All Free Biology MCQs with Answers

Every Biology question in the bank, across all chapters, each with the correct answer and a written explanation. Free and unlimited, with no account needed.

19,844 questions · page 930 of 993

  • A. Osteomalacia (soft bones)
  • B. Disc slip
  • C. Arthritis
  • D. Spondylosis

Explanation: Options [A] osteomalacia is a group of diseases in which bone resorption outpaces bone deposit[ it means there is more bone depletion than…

Correct answer: Spondylosis
  • A. Sciatica
  • B. Spondylosis
  • C. Rheumatoid arthritis
  • D. Rickets

Explanation: Rheumatoid arthritis (RA) is an autoimmune disorder that causes chronic inflammation of the joints.

Correct answer: Rheumatoid arthritis
  • A. Nerve cells.
  • B. Brain cells.
  • C. Bone cells.
  • D. None of these.

Explanation: b) Brain cells: Brain cells, which include various types of neurons and glial cells, also contain a significant amount of water due to…

Correct answer: Brain cells.
  • A. 20
  • B. 40
  • C. 85
  • D. 90

Explanation: Bone is a complex and rigid connective tissue that contains various components, including cells, fibres, and minerals.

Correct answer: 20
  • A. Water
  • B. Protein
  • C. Carbohydrates
  • D. Lipids

Explanation: Water (Option A) forms almost three-fourths of the body by weight. The human body is composed of a significant amount of water, which…

Correct answer: Water
  • A. Hydrophilic exclusion
  • B. Hydrophobic
  • C. Specific heat capacity exclusion
  • D. Heat of vaporization

Explanation: Biologically, the hydrophobic interactions (Option B) play key roles in maintaining the integrity of lipid bilayer membranes.

Correct answer: Hydrophobic
  • A. Reduction
  • B. Oxidation
  • C. Redox
  • D. None of above

Explanation: The specific heat of vaporization of water plays an important role in the regulation of heat produced by OxidationSpecific heat of…

Correct answer: Oxidation
  • A. Nonpolar covalent bonds
  • B. Polar covalent bonds
  • C. Hydrogen bonds
  • D. Covalent bonds

Explanation: For water to vaporize (turn from a liquid into a gas), the type of bond that must be broken is Hydrogen bondsWater molecules are held…

Correct answer: Hydrogen bonds
  • A. Neurospora.
  • B. Aspergillus.
  • C. Griseofulvin.
  • D. Lovastatin.

Explanation: Statins are the most common medicine for high cholesterol. They reduce the amount of cholesterol your body makes.

Correct answer: Lovastatin.
  • A. Soybean.
  • B. Digitalis lanata
  • C. Cinchona ledgeriana.
  • D. Luceferin.

Explanation: Quinine is a bitter compound that comes from the bark of the cinchona tree.

Correct answer: Cinchona ledgeriana.
  • A. DNA polymerase I
  • B. DNA ligase
  • C. DNA polymerase ITI
  • D. Taq polymerase

Explanation: Explanation:Taq polymerase is very thermo stable as it is derived from bacteria Thermophilus aquaticus that lives in hot geysers.

Correct answer: Taq polymerase
  • A. Wheat Plant
  • B. Tobacco Plant
  • C. Rice Plant
  • D. Corn Plant

Explanation: Explanation:Tobacco plants are commonly used for producing antigens to treat non-hodgkin lymphoma.Wheat is not commonly used for producing…

Correct answer: Tobacco Plant
  • A. Ribosomes
  • B. Plasmids
  • C. Nucleoids
  • D. Mesosomes

Explanation: Explanation:This option is correct because plasmids are one of the most useful and important vectors.

Correct answer: Plasmids
  • A. Restriction enzymes
  • B. cDNA (complementary DNA)
  • C. Vector
  • D. Reverse transcriptase

Explanation: [A] Restriction enzymes recognize a specific sequence of nucleotides in double stranded DNA and cut the DNA at a specific location [B]…

Correct answer: Reverse transcriptase
  • A. pSC 101
  • B. pCR 101
  • C. pBR 322
  • D. pBR 233

Explanation: [A] pSC101 has antibiotic resistance for tetracycline only[C] pBR322 has antibiotic resistance gene for both Tetracycline and…

Correct answer: pBR 322
  • A. Cultural Control
  • B. Biological Control
  • C. Pesticides Control
  • D. Insecticides Control

Explanation: Control of pests by means of introducing natural predators or diseases affecting the pests comes under the umbrella of biological control.

Correct answer: Biological Control
  • A. Pasteurization
  • B. Integrated disease management
  • C. Biological control
  • D. Genetic engineering

Explanation: Control of pests by means of introducing natural predators or diseases affecting the pests comes under the umbrella of biological control.

Correct answer: Biological control
  • A. Antigen
  • B. Biocidal
  • C. Antiseptics
  • D. Antibiotics

Explanation: Antibiotics are chemicals which are produced by micro-organisms, and are particularly adept at destroying bacteria

Correct answer: Antibiotics
  • A. Clonal plants
  • B. Transgenic plants
  • C. Biotech plants
  • D. Tissue cultured plants

Explanation: The term transgenic indicates an organism that contains genetic material from a foreign source.

Correct answer: Transgenic plants
  • A. Complementary DNA
  • B. Recombinant DNA
  • C. Chimeric DNA
  • D. Plasmid DNA

Explanation: The DNA molecule formed from messenger-RNA (mRNA) by reverse transcriptase is called complementary DNA (cDNA).

Correct answer: Complementary DNA