#Question id: 12311
#Unit 10. Ecological Principles
#Question id: 3844
#Unit 3. Fundamental Processes
The lagging strand is characterized by a series of short segments of DNA (Okazaki fragments) that will be joined together to form a finished lagging strand. The experiments that led to the discovery of Okazaki fragments gave evidence for which of the following ideas?
#Question id: 3602
#Unit 8. Inheritance Biology
Mendel crossed Yellow, round and tall pea plants ( YYRRTT) with green, wrinkle and dwarf ones ( yyrrtt). The F1 plants were all yellow, round tall. These F1 plants were cross with YyrrTT. Which of the following proportional of phenotype in progeny?
#Question id: 462
#Unit 1. Molecules and their Interaction Relevant to Biology
The formation of acetyl CoA is driven to completion by
#Question id: 643
#Unit 1. Molecules and their Interaction Relevant to Biology
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.