All Free Biology MCQs with Answers
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19844 questions · page 537 of 1985
5361. The insertion of genetic material into human cells for the treatment of a disorder is called:
- A. Gene cloning
- B. Gene pharming
- C. Gene therapy
- D. Gene sequencing
Explanation: Gene therapy is a technique that uses a gene(s) to treat, prevent or cure a disease or medical disorder. Often, gene therapy works by adding new copies of a gene that is broken, or by replacing a defective or missing gene in a patient's cells with a healthy version of that gene.
Correct answer: Gene therapy5362. The disease not treated by Ex-vivo gene therapy is:
- A. SCID
- B. Diabetes
- C. Hypercholesterolemia
- D. All of the above
Explanation: Among the many gene therapy trials, one is for the treatment of familial hypercholesterolemia a condition that develops when liver cells lack a receptor for removing cholesterol from the blood. The high levels of blood cholesterol make the patient subject to fatal heart attacks at a young age. In a newly developed procedure, a small portion of the liver is surgically excised and infected with a retrovirus containing a normal gene for the receptor. Several patients have experienced a lowering of serum cholesterol levels following this procedure
Correct answer: Hypercholesterolemia5363. The enzyme ADA is involved in maturation of:
- A. RBC
- B. Platelets
- C. Lymphocyte
- D. Macrophages
Explanation: Adenosine deaminase (ADA) is involved in the maturation of T and B cells and, therefore, they are subjected to life-threatening infections.
Correct answer: Lymphocyte5364. The organism used as a vector during the treatment of SCID by gene therapy is:
- A. Plasmids
- B. Phage
- C. Retroviruses
- D. None of the above
Explanation: Retroviruses are commonly employed as the vectors for gene therapy, due to their unique ability to penetrate the cells of the patients.
Correct answer: Retroviruses5365. The genes for the treatment of SCID are introduced in:
- A. Bone marrow
- B. Heart
- C. Liver
- D. None of the above
Explanation: Patients undergoing SCID-X1 gene therapy first have their blood stem cells collected from their blood and treated in a highly specialized laboratory. A self-inactivating virus, specially designed for safety, is used as a carrier to insert a correct version of the faulty IL2RG gene into the patient's stem cells.
Correct answer: Bone marrow5366. The hypercholesterolemia causes at young age:
- A. Diabetes
- B. Blood pressure
- C. Heart attack
- D. All of the above
Explanation: The high levels of blood cholesterol make the patient subject to fatal heart attacks at a young age.
Correct answer: Heart attack5367. The genes for the treatment of hypercholesterolemia are introduced in:
- A. Bone marrow
- B. Heart
- C. Liver
- D. None of the above
Explanation: In a newly developed procedure, a small portion of the liver is surgically excised and infected with a retrovirus containing a normal gene for the receptor. Several patients have experienced a lowering of serum cholesterol levels following this procedure.
Correct answer: Liver5368. The gene therapy in cancer makes the patient tolerant for:
- A. Radiotherapy
- B. Chemotherapy
- C. Endoscopy
- D. Exoscopy
Explanation: Gene therapy is also being done to cancer patients, which makes them more tolerant of chemotherapy.
Correct answer: Chemotherapy5369. These are used in angioplasty:
- A. Balloon
- B. Plasmids
- C. Gene therapy
- D. All of the above
Explanation: During coronary artery angioplasty, a balloon catheter is sometimes used to open up a closed artery. Unfortunately, the artery has a tendency to close up once again. But investigators have come up with a new procedure. The balloon is coated with a plasmid that contains a gene for vascular endothelial growth factor. The expression of the gene, which promotes the proliferation of blood vessels to bypass the obstructed area, has been observed in at least one patient.
Correct answer: All of the above5370. Which of the following diseases is not treated by in-vivo gene therapy?
- A. Hemophilia
- B. Diabetes
- C. Parkinson's diseases
- D. None of the above
Explanation: Perhaps it will be possible to use in vivo therapy to cure hemophilia, diabetes, Parkinson's disease, or AIDS.
Correct answer: None of the above