Tag: zoology

Questions Related to zoology

Enzyme adenosine deaminase is deficient in .......... genetic disorder.

  1. Alzheimers disease

  2. Muscular dystrophy

  3. SCID

  4. Colour blindness


Correct Option: C
Explanation:

The correct option is C


Severe combined immunodeficiency (SCID) is an X-limbed inherited disorder of the immune system, that occurs almost exclusively in males. Boys with x-linked SCID are prone to recurrent and persistent infections because they 
lack the necessary immune cells to fight off certain bacteria, viruses, etc, It is 
caused by a disorder of or by a deficiency of the adenosine deaminase which is very necessary for lymphocyte development.

First clinical application of gene therapy was used in 1992 over a four year old girl for

  1. Adenosine deficiency

  2. Adenine deficiency

  3. Growth deficiency

  4. Adenosine deaminase deficiency


Correct Option: D

The genetic defect adenosine deaminase (ADA) deficiency may be cured permanently by

  1. Introducing bone marrow cells producing (ADA) into cells at an early embryonic stage.

  2. Administrating adenosine deaminase activators.

  3. Periodic infusion of genetically engineered lymphocytes having functional ADA cDNA.

  4. Enzyme replacement therapy.


Correct Option: A

A genetic disorder can be cured through 

  1. Gene therapy

  2. rDNA technology

  3. Embryo transfer

  4. Hybridoma technology


Correct Option: A

Due to .......... therapy changes would be heritable.

  1. Magnetic therapy

  2. Somatic cell gene therapy

  3. Germ line gene therapy

  4. Chemotherapy


Correct Option: C
Explanation:
Gene therapy is treating the diseases by modifying the gene expression or inserting the deficient gene therapeutically into the patients cells. Gene therapy is of two types, somatic gene therapy and germline gene therapy.
In somatic gene therapy, gene manipulation is done in the cells which will affect the patient but it will not be inherited. In germline gene therapy, gene manipulation is done in the germ cells or the gametes that will be used to conceive. The modified germ cells will produce the gametes having the inserted gene and on fertilisation will produce a zygote that will form the individual in which each and every cell will have the manipulated gene, because every cell descendes from the zygote. Thus, the changes will be heritable.
So, the correct answer is C.

Gene therapy is treatment done on

  1. Adults only

  2. Child or embryo only

  3. Pregnant mothers only

  4. Persons of any age and condition


Correct Option: D

Which of the following statements is incorrect about gene therapy in ADA deficiency?

  1. Lymphocytes from patient's blood are taken out and cultured.

  2. A functional ADA cDNA is introduced into these lymphocytes.

  3. Lymphocytes are then introduced in the body of patient.

  4. Patient does not require periodic infusion of genetically engineered lymphocytes.


Correct Option: D
Explanation:
As a first step towards gene therapy, lymphocytes from the blood of the patient are grown in a culture outside the body. A functional ADA-cNDA  (using a retroviral vector) is then introduced into these lymphocytes, which are subsequently returned to the body of the patient. However, as these cells are not immortal, the patient requires periodic infusion of such genetically engineered lymphocytes.
So, the correct answer is 'Patient does not require periodic infusion of genetically engineered lymphocytes'.

Identify the wrong statements :


a) Genetic modifications in plants helped to reduce post-harvest losses
b) In Tobacco, cry genes are introduced against nematodes
c) In gene therapy, healthy genes are inserted into persons cells and tissues to treat diseases
d) Injustice, inadequate compensation, and benefit-sharing are related to molecular diagnosis

  1. a, b, c

  2. b, c, d

  3. a, b, d

  4. a, c, d


Correct Option: B

Adenosine deaminase deficiency can be permanently cured by which of the following methods?

  1. Bone marrow transplantation

  2. Enzymes replacement therapy

  3. Gene therapy at early embryonic stages

  4. All of these


Correct Option: C
Explanation:

Adenosine deaminase (ADA) deficiency can be treated by bone marrow transplantation, or by enzyme replacement therapy, in which functional ADA is given to the patient by injection. But permanent treatment can be done by introduction of gene isolated from bone marrow cells, which produces ADA, into the cells of the patient at early embryonic stage.

..........is the transfer of normal genes into body cells to correct a genetic defect.

  1. gene therapy

  2. gene mutation

  3. nucleic acid hybridization

  4. reverse transcription


Correct Option: A
Explanation:

Gene therapy is a collection of methods that allow correction of a gene defect that has been diagnosed in a child/embryo. In this method, genes are inserted into a person's cells and tissues to treat a disease. Correction of a genetic defect involves delivery of a normal gene into the individual or embryo to take over the function of and compensate for the non-functional gene.

So, the correct option is 'gene therapy'.