Molecular Biology and Genetics MCQs

A dioecious plant has XX sexual genotype for female and XY for male. After double fertilization, what would be the genotype of the embryos and endosperms?

An in vitro translation system can synthesize peptides in all three reading frames of the RNA template. When 5' - UCUCUCUC-(UC)n-UCUCUCUC - 3' was used as the template in this in vitro translation system, the synthesized peptides contained 50% each of serine and leucine. When 5' - CCUCCUCCU-(CCU)n-CCUCCU - 3' was used as the template, the synthesized peptides contained 33.3% each of serine, leucine, and proline. Deduce the codon for proline.

During protein synthesis, tRNAs are not involved in

If the nucleotide composition (%) of a viral genome is A = 10, U = 20, C = 40 and G = 30, which one of the following is this genome?

Which set of the following events occurs during the elongation step of translation? P. Attachment of mRNA with the smaller subunit of ribosome Q. Loading of correct aminoacyl-tRNA into the A site. R. Formation of a peptide bond between the amino acyl-tRNA in the A site and the peptide chain that is attached to the peptidyl-tRNA in the P site. S. Dissociation of the ribosomal subunits. T. Translocation of peptidyl-tRNA from the A site to the P site of the ribosome.

In a genetic cross between the genotypes WWXX and wwxx, the following phenotypic distributions were observed among the F2 progeny: WX, 562; wx, 158; Wx, 38; and wX, 42. Likewise, a cross between XXYY and xxyy yielded the following results: XY, 675; xy, 175; Xy, 72; and xY, 78. Similarly, a cross between WWYY and wwyy yielded: WY, 292; wy, 88; Wy, 12; and wY, 8. In all the genotypes, capital letters denote the dominant allele. Assume that the F1 progeny were self-fertilized in all three crosses. Also, double cross-over does not occur in this species. Which of the following is correct?

The major groove of DNA is lined by

An example for template independent DNA polymerase is

Synteny refers to