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.
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 is the correct matching of three items and their grouping category?
Items |
Group |
Malleus, incus, cochlea |
Ear ossicles |
Items |
Group |
IIium, ischium, pubis |
Coxal bones of pelvic girdle |
Items |
Group |
Actin, myosin, Rhodopsin |
Muscle proteins |
Items |
Group |
Actin, myosin, Rhodopsin |
Muscle proteins |
Removal of introns and joining the exons in a defined order in transcription unit is called
splicing
tailing
transformation
transformation
Study the pedigree chart given below.
what does it show?
Inheritance of a sex-linked inborn error of metabolism like phenylketonuria
Inheritance of a condition like phenylketonuria as an autosomal recessive trait
The pedigree chart is wrong as this is not possible
The pedigree chart is wrong as this is not possible