Test: Questions for GATE aspirants
Description: Students preparing for entrance examinations like CSIR, UGC NET, GATE and other entrance examinations for various PG courses will find these questions very helpful.
Keywords: Gate, CSIR, PG, NET, Biology, Lifesciences, entrance examinations
Which of the following cannot be formed from acetyl CoA in a single step?
acetyl-CoA + oxaloacetate + H2O ------------------------→ citrate + CoA-SH Oxaloacetate is the first substrate to bind to the enzyme. This induces the enzyme to change its conformation, and creates a binding site for the acetyl-CoA.
aceto acetyl CoA
Which of the following inhibitor uncouples electron transport and oxidative phosphorylation?
The identification of a compound on the basis of absorption of a particular wavelength of light is done through
A spectrophotometer is employed to measure the amount of light that a sample absorbs.
Milk casein is a
Casein is the name for a family of related phosphoprotein proteins (αS1, αS2, β, κ). These proteins are commonly found in mammalian milk, making up 80% of the proteins in cow milk and between 60% and 65% of the proteins in human milk.
Fibrinogen is converted to fibrin by
Km is equal to
The Michaelis constant Km is the substrate concentration at which the reaction rate is half of Vmax.
[s] when V = Vm
[s] when V= 0
[s] when V = I/2 Vm
Autonomous extrachromosomal circular DNA molecules are known as
Lymphocytes that activate B cells and T cells are
T helper cell (TH cells) assist other white blood cells in immunologic processes, including maturation of B cells into plasma cells and memory B cells, and activation of cytotoxic T cells and macrophages, among other functions.
Activator B cells
Helper T cells
Cytotoxic T cells
The regions of an antibody that determine its general role, or effector function are its
Effector functions are determined by the constant regions of the heavy chains (Fc). The effector functions of immunoglobulins are mediated by this part of the molecule. Normally the ability of an antibody to carry out an effector function requires the prior binding of an antigen.
variable (v) regions
mutated (m) regions
bifurcated (b) regions
Which of the following is a hypoglycemic hormone?
The region on t-RNA which recognizes the codon on m-RNA is the
amino acid acceptor arm
An amino acid which is not an intermediate in Krebs’ urea cycle is
The chloride shift involves
Chloride shift is the simultaneous exchange of chloride (Cl−) and bicarbonate (HCO3−) between plasma and the erythrocytes occurring whenever HCO3− is generated or decomposed within the erythrocytes.
H+ leaving RBC for each CO2 that enters
HCO3 - Ieaying RBC in exchange for Cl-
K+ accompanying each HCO3 - ion
Proto oncogenes are
A proto-oncogene is a normal gene that can become an oncogene due to mutations or increased expression.
Present exclusively in viruses
Present in fully developed cancer cells
The genes present in normal cells similar to viral oncogenes
Present in murine sarcoma virus
Non-cyclic photophosphorylation produces all of the following except
The minimum number of nucleotide—residues required on an m-RNA to code for a polypeptide of 90 amino acid residues is
Three nucleotides on mRNA code for an amino acid. Here we have 90 AA that is 90x3 = 270 bases.
Cholic acid is
a bile acid
a bile pigment
a precursor of cholesterol
Actinomycin D is an inhibitor of
Actinomycin D is effective as an inhibitor of transcription. It does this by binding DNA at the transcription initiation complex and preventing elongation by RNA polymerase.
All the above
Complete aerobic oxidation of one molecule of acetyl coenzyme A produces
Which of the following is classified as a high-energy compound?
1, 3- bis-phospho glycerate