#Question id: 763
#SCPH28 | Zoology
Which of the following could be an effect of miRNA regulation?
#Question id: 3668
#SCPH01 Biochemistry
In most plasmids, the genes for proteins required for replication are located very close to the ______________ at which their gene are transcribed.
#Question id: 4827
#SCPH28 | Zoology
A cross between individuals with genotypes AaBbX aabb produces the following progeny:
AaBb - 83, aaBb- 21, Aabb- 19, aa bb -77
Which of the following statements is true?
#Question id: 19455
#SCPH01 Biochemistry
#Question id: 643
#SCPH05 I Biotechnology
The hydrolysis of lactose is catalysed by b-galactosidase as given below
Which of the following could be correct mechanism for this hydrolysis reaction?
A. Nucleophilic attack by the carboxylate group of Glu/Asp on the C-1 carbon atom of the galactose moiety within glucose, releasing glucose and forming an intermediate with the galactose linked to the enzyme through an ester linkage. Water then attacks this carbon atom, displacing the glutamate carboxylate and releasing galactose.
B. Electrophilic attack by the carboxylate group of Glu/Asp on the C-1 carbon atom of the galactose moiety within glucose, releasing glucose and forming an intermediate with the galactose linked to the enzyme through an ester linkage. Water then attacks this carbon atom, displacing the glutamate carboxylate and releasing galactose.
C. Nucleophilic attack by the carboxylate group of Lys/Arg/His or bivalent cation on the C-1 carbon atom of the galactose moiety within glucose, releasing glucose and forming an intermediate with the galactose linked to the enzyme through an ester linkage. Water then attacks this carbon atom, displacing the glutamate carboxylate and releasing galactose.