Health Care > EXAM > CBSE Biochem (402 Questions with 100% Correct Answers) with COMPLETE SOLUTION (All)

Also available in bundle ( Click Here )

CBSE Biochem (402 Questions with 100% Correct Answers) with COMPLETE SOLUTION

Document Content and Description Below

Lesch-Nyhan Syndrome: what causes it and what are manifestations? - ✔✔HGPRT deficiency in purine salvage pathway (this enzyme normally converts hypoxanthine to IMP and guanine to GMP). This defi... ciency leads to excessive Uric acid production and de novo purine synthesis. It is X linked recessive. Symptoms: hyperuricemia, gout, aggression / self mutilation, mental retardation, dystonia. Treatment for Lesch-Nyhan? - ✔✔Allopurinol / febuxostat second line. Both of these drugs inhibit xanthine oxidase, which converts hypoxanthine to xanthine and xanthine to uric acid. Adenosine Deaminase Deficiency: what is it, what effects does it have? - ✔✔ADA is required for degradation of adenosine and deoxyadenosine--dATP builds up and is toxic to lymphocytes, which is why this disease is a major cause of SCID--severe combined immunodeficiency (Autosomal recessive). Why is purine salvage important? - ✔✔Because in some tissues, de novo purine synthesis is not possible. How are nucleotide monophosphates created? - ✔✔Activated ribose-5-phosphate (PRPP) is added to bases by phosphoribosyltransferases (HGPRT and APRT are the two types of this enzyme). tRNA Wobble: what is it and it causes which type of mutation? - ✔✔An unusual pairing of bases in the third position of the codon--causes silent mutation. Sickle Cell Anemia is caused by which type of mutation? - ✔✔Missense mutation--valine replaces glutamic acid. Tay-Sachs and Duchenne Muscular Dystrophy are caused by which mutation type? - ✔✔FrameshiftXeroderma Pigmentosum: is caused by a defect in what specifically? - ✔✔Nucleotide excision repair--pyrimidine dimers are not repaired (caused by UV exposure). In nucleotide excision repair, bulky helix-disturbing lesions are repaired by endonucleases. This occurs during G1 of cell cycle. [Show More]

Last updated: 2 years ago

Preview 1 out of 47 pages

Buy Now

Instant download

We Accept: