Differentiation of organs and tissues in a developing organism, is associated with:

(1) developmental mutations

(2) differential expression of genes

(3) lethal mutations

(4) deletion of gens

Regulation of gene expression in eukaryotes cannot take place at

(1)primary transcript level

(2)splicing level

(3)transport of m-RNA from nucleus to cytoplasm

(4)replication level

In eukaryotes the gene expression is regulated at:
A. Transcriptional level
B. Processing level
C. Transport of mRNA from nucleus to the cytoplasm
D. Translational level
(1) A, C               

(2) A, B, C, D                 

(3) B, C, D                     

(4) A, B, C

One gene-one enzyme relationship was established for the first time in:

1. Neurosporacrassa

2. Salmonella typhimurium

3. Escherichia coli

4. Diplococcuspneumonia