#Question id: 673
#Unit 1. Molecules and their Interaction Relevant to Biology
How many complete turns are there in an ideal α-helix that contains 15 amino acids and has a pitch of 0.54 nm and a rise of 0.15 nm?
#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.
#Question id: 8773
#Unit 9. Diversity of Life Forms
Which eukaryotic kingdom includes members that are the result of endosymbioses that included an ancient aerobic bacterium and an ancient cyanobacterium?
#Question id: 11981
#Unit 10. Ecological Principles
#Question id: 3366
#Unit 11. Evolution and Behavior
Red-Green color blindness is an X-linked recessive disorder. In a population which is in the Hardy- Weinberg equilibrium, the incidence of occurrence of this in males is 2:2000. What will be the expected incidence of affected homozygous females?