The DNAstrand with 3'-5' polarity only is trancribed and not the other because the RNA-polymerase can polymerize RNA only in 5'-3' direction.

Sometimes cattle or human beings give birth to their young ones that are having different sets of oranges like limbs/position of eye, etc.It happens due to the disturbance in coordinated regulation of expression in sets of genes, which are associated with organ development

1. Functional mRNA of structural genes need not always include all of its exons.This alternate splicing of exons is sex-specific , issue-specific and even development stage-specific.
2. By such alternate splicing of exons, a single gene may encode for several ios proteins and/ or proteins of similar class.In absence of such a kind od splicing, there should have been new genes for every protein/isoprotein.Such an extravagance has been avoided in natural phenomena by alternative splicing.

A polynucleotide chain comprises of a long chain of nucleotides joined by 3'-5' phosphodiester linkages.Such a polymer has at one a free phosphate moiety at 5'-end of ribose sugar.This end of polymer is referred to as 5'-end.Similarly, at the other end of the polymer, the pentose sugar has a free 3'-OH group.This end of polymer is referred to as 3'-end.

(a) Genetic RNA-Double stranded RNA of mammalian reovirus
Non-genetic RNA-Ribosomal RNA, messenger RNA or transfer RNA
(b)Prolaryotic mRNA is short lived and hardly undergoes processing(capping, methylation and polyadenylation)to from comparatively stable mRNA.

(a)Correct
(b)The genetic code is non-ambiguous
(c)The genetic code is degenerate
(d)Transfer RNA(tRNA) carry amino acids to mRNA codons and used again and again in translation
(e)Correct
(f)Correct

The gel electrophoresis is carried out by loading the slab of agarose gel with DNA fragments and placing in an electric field.DNA, being negatively charged moves towards positively charged electrode.Larger fragments move slowly than smaller ones.Thus, the DNA fragments get separated into individual bands according to their molecular size.

The core part of nucleosome comprises of 8 Histone molecules.DNA molecules is negatively charged whereas histone octomer is positively charged.Therefore, negatively charged DNA binds with the positively charged histone octomer

(a) Continuous synthesis of DNA
(b) Discontinuous synthesis of DNA

(i) Replication of DNA occurs in small replication forks, because DNA is such a long molecule that the separation of the two strands along its entire length requires a very high amount of energy.
(ii) DNA polymerase can catalyse the polymerisation of nucleotides only in \({ 5 }^{ ' }\rightarrow { 3 }^{ ' }\) direction.So on the template strand with \({ 3 }^{ ' }\rightarrow { 5 }^{ ' }\) polarity, DNA replication is continuous.On the template strand with \({ 5 }^{ ' }\rightarrow { 3 }^{ ' }\) polarity, DNA synthesis occurs in short stretches as the opening of replication fork continues; later these short stretches are joined by the action of DNA ligases
(iii) Replication of DNA does not initiate randomly, and DNA polymerases on their own cannot initiate replication.So, there is a specific sequence on DNA, called origin of replication; DNA polymerase binds to it and continues the process.