Q-201. Rapid method of chromosome identification in intersex is:
a) PCR
b) FISH
c) Karyotyping
d) Single-strand conformational polymorphism (SSCP)
Answer: FISH
Explanation:
FISH (Fluorescent in situ hybridization) is a technology utilizing fluorescent labeled DNA probes to detect or confirm gene/ chromosome abnormalities.
A good example is aneuploidy screen test which is performed on amniotic fluid cells.
The most important advantage of FISH is that it can be done very rapidly, if necessary, usually within 24 hours.
Q-202. Which of the following is not required in PCR?
a) d-NTP
b) Primer
c) Radio-labelled DNA probe
d) Taq polymerase
Answer: Radio-labelled DNA probe
Explanation:
PCR (Polymerase Chain Reaction) is a revolutionary method developed by Kary Mullis in the 1980s.
PCR is based on using the ability of DNA polymerase to synthesize new strand of DNA complementary to the offered template strand.
RT-PCR (Reverse Transcription PCR) is PCR preceded with conversion of sample RNA into cDNA with enzyme reverse transcriptase.
Material required for PCR:
DNA template
Primers
DNA polymerase (Taq polymerase)
Deoxy-ribo-nucleoside tri-phosphates (d-NTPs)
Buffer solution
Divalent cations- Mg++ or Mn++ (Generally Mg++ is used)
Monovalent cation- K+
Q-203. Y chromosome is:
a) Acro-centric
b) Meta-centric
c) Sub-meta-centric
d) Telo-centric
Answer: Acro-centric
Explanation:
X chromosome: Sub-Meta-centric chromosome
Y chromosome: Acro-centric
Humans do not posses any telo-centric chromosome.
Q-204. All the following reactions occur in the mitochondria except:
a) EMP Pathway
b) Krebs cycle
c) Electron transport chain
d) Fatty acid oxidation
Answer: EMP Pathway
Explanation:
EMP Pathway or Glycolysis- Cytosol
HMP Shunt- Cytosol
Fatty acid synthesis- Cytosol
Kreb’s cycle- Mitochondria
Electron transport Chain- Mitochondria
Fatty acid oxidation- Mitochondria
Q-205. Enzymes of glycolysis are present in:
a) Cytosol
b) Mitochondria
c) Nucleus
d) Cell membrane
Answer: Cytosol
Explanation:
EMP Pathway or Glycolysis- Cytosol
HMP Shunt- Cytosol
Fatty acid synthesis- Cytosol
Kreb’s cycle- Mitochondria
Electron transport Chain- Mitochondria
Fatty acid oxidation- Mitochondria
Q-206. Enzyme responsible for complete oxidation of glucose to CO2 + H2O is present in
a) Cytosol
b) Mitochondria
c) Endoplasmic reticulum
d) Lysosomes
Answer: Mitochondria
Explanation:
Kreb’s cycle is the final pathway for complete oxidation of glucose to CO2 + H2O.
Q-207. Final product of purine metabolism in non primate mammals:
a) Ammonia
b) Urea
c) Uric acid
d) Allantoin
Answer: Allantoin
Explanation:
Inside the cells, purine nucleotides are sequentially degraded by specific enzymes, with uric acid as end product of pathway.
Mammals other than primates oxidize uric acid further to Allantoin, which in some animals other than mammals, may be further degraded to urea or ammonia.
Q-208. Ammonia is formed from which of the following amino acid in kidney?
a) Glutamine
b) Alanine
c) Methionine
d) Glycine
Answer: Glutamine
Explanation:
The kidneys form ammonia from glutamine by the action of renal glutaminase.
Most of this ammonia is excreted into the urine as NH4+, which provides an important mechanism for maintaining the body’s acid base balance.
Q-209. All of the following are essential amino acids except:
a) Lysine
b) Methionine
c) Leucine
d) Alanine
Answer: Alanine
Explanation:
Essential amino acids:
Leucine, Iso-Leucine, Lysine, Methionine
Phenylalanine, Threonine, Tryptophan, Valine
Semi-essential amino acids:
Arginine and Histidine
Ketogenic amino acids:
Leucine and Lysine
Glucogenic and Ketogenic amino acids:
Iso-Leucine, Phenylalanine
Tryptophan, Tyrosine
Q-210. Triglyceride content is highest in:
a) LDL
b) VLDL
c) Chylomicrons
d) HDL
Answer: Chylomicrons
Explanation:
Chylomicrons- Maximum content of triglyceride (Over all and exogenous)
VLDL- Maximum content of endogenous triglyceride
LDL- Maximum content of cholesterol