Which one of the following is commonly used in the transfer of foreign DNA into crops plants?
Trichoderma hazianum
Meloidogyne incognita
Agrobacterium tumefaciens
Agrobacterium tumefaciens
Removal of introns and joining the exons in a defined order in transcription unit is called
splicing
tailing
transformation
transformation
Whose experiments cracked the DNA and discovered unequivocally that is genetic code is a triplet?
Nirenberg and Mathaei
Hershey and Chase
Morgan and Sturtevant
Morgan and Sturtevant
A.
Nirenberg and Mathaei
The existence of a triplet code was simply an assumption till 1961 when Nirenberg and Methaei proved its existence by experiment. They were able to synthesise artificial mRNA, which contained only one nitrogenous base, ie, uracil. This synthetic poly-U sequence was then placed in a cell-free system containing protein synthesizing enzymes (extracted from bacterium E. coil) and 20 amino acids together with necessary ATP. During the process, a small polypeptide molecule was produced, which was formed by the linking of phenylalanine. This issuggested that UUU is code for phenylalanine. Nirenberg got Nobel Prize for his contributions.
Seminal plasma in human is rich in
fructose, calcium and certain enzymes
fructose and calcium but has no enzymes
glucose and certain enzymes but has no calcium
glucose and certain enzymes but has no calcium
Synapsis occurs between
a male and female gamete
mRNA and ribosomes
spindle fibres and centromere
spindle fibres and centromere
select the incorrect statement from the following
Linkage is an exception to the principle of independent assortment in heredity
galactosemia is an inborn error of metabolism
small population size results in a random genetic drift in a population
small population size results in a random genetic drift in a population
Which one of the following types of organisms occupy more than one trophic level in a pond ecosystem?
Phytoplankton
Fish
Zoonplankton
Zoonplankton
Use of antihistamines and steroids give a quick relief from
allergy
nausea
cough
cough
Which one is the wrong pairing for the disease and its causal organism?
Late blight of potato - Alternaria solani
Black rust of wheat - puccinia graminis
Loose smut of wheat - Ustilago nuda
Loose smut of wheat - Ustilago nuda
What is true about Bt toxin
The inactive protoxin gets converted into active form in the insect gut
Bt protein exists as active toxin in the bacillus
The activated toxin enters the ovaries of the pets to sterilise it and thus prevent its multiplication
The activated toxin enters the ovaries of the pets to sterilise it and thus prevent its multiplication