All Free Biology MCQs with Answers
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19844 questions · page 571 of 1985
5701. The procedure of transgenic animals has been used to produce larger:
- A. Fishes and cows
- B. Rabbits and sheeps
- C. Cows and pigs
- D. Fishes, cows, pig, rabbits and sheep
Explanation: It is possible by tempering their genetic makeup.
Correct answer: Fishes, cows, pig, rabbits and sheep5702. Genes that code for _ proteins are incorporated into the animal's DNA and the proteins appear in the animal's milk.
- A. Therapeutic
- B. Therapeutic and diagnostic
- C. Diagnostic
- D. Osmotic
Explanation: Some proteins are used for treatment of diseases. They are called therapeutic proteins and diagnostic proteins as they are used to diagnose and treat diseases. Both are being produced as biotechnology products.
Correct answer: Therapeutic and diagnostic5703. There are plans to produce drugs by transgenic animals, for the treatment of:
- A. Cystic fibrosis
- B. Blood diseases
- C. Cancer
- D. Cystic fibrosis, Cancer & Blood diseases
Explanation: In future it is being envisioned to get drugs prepared by transgenic animals against cystic fibrosis, cancer and blood diseases.
Correct answer: Cystic fibrosis, Cancer & Blood diseases5704. Although each cell contains a copy of all the genes of that genome, certain genes are:
- A. Amplified in mature specialized cells
- B. Turned off in mature specialized cells
- C. Lost in mature specialized cells
- D. Mutated in mature specialized cells
Explanation: When a cell is assigned a specialized job, only those genes remain active which are associated with that particular job, rest are turned off, however, they can be switched on again if needed.
Correct answer: Turned off in mature specialized cells5705. Insertion of genetic material into human cells for treatment of a disorder is called:
- A. Genetic engineering
- B. Gene therapy
- C. Biotechnology
- D. Gene mutation
Explanation: Treating some genetic disorder by replacing a faulty gene with normal gene is called gene therapy.
Correct answer: Gene therapy5706. The children suffering from SCIDS lack an enzyme called:
- A. Adenosine deaminase
- B. Homogentisic and hydroxylase
- C. Phenylalanine hydroxylase
- D. Homogentisic and dehydrogenase
Explanation: Such children lack an enzyme adenosine deaminase (ADA) that is involved in the maturation of T and B cells and therefore, they are subjected to life threatening infections.
Correct answer: Adenosine deaminase5707. Both T and B cells get maturation by the involvement of gene called:
- A. Phenyl alanine hydroxylase
- B. ADA
- C. Homogentisic acid dehydrogenase
- D. Phospho hexokinase
Explanation: ADA (adenosine deaminase) is involved in the maturation of T and B cells and therefore, the person lacking it are subjected to life threatening infection.
Correct answer: ADA5708. For treatment of SCIDS, the bone marrow stem cells are infected with a retrovirus that carries:
- A. A normal enzyme
- B. A mutant gene for the enzyme
- C. A normal gene for the enzyme
- D. A normal gene for T and B cells
Explanation: Retrovirus acts a vector and carrier a normal gene for the synthesis of ADA enzyme with its DNA (recombinant DNA).
Correct answer: A normal gene for the enzyme5709. Bone marrow stem cells are preferred for gene therapy of SCIDS, because:
- A. They are larger in size
- B. They are numerous in number
- C. They divide to produce more cells with same gene
- D. They store much enzyme inside them
Explanation: Stem cells keep on dividing by mitosis and in this way the number is continuously added up which gradually overcome the immune deficiency.
Correct answer: They divide to produce more cells with same gene5710. If the patient dies due to numerous infections of the respiratory tract, it means he/she suffered from:
- A. SCIDS
- B. Cystic fibrosis
- C. Hypercholesterolemia
- D. Parkinsonism
Explanation: Cystic fibrosis patients lack a gene that codes for trans-membrane carrier of chloride ions.
Correct answer: Cystic fibrosis