Molecular Basis of Inheritance Test - 42

• The method by which information reaches from DNA to RNA is called transcription. 
• The translation is the process by which a cell makes proteins using the genetic information carried in mRNA.
  
• Genetic transformation involves the transfer and incorporation of foreign DNA into a host genome. 
  
• Transduction is the process by which a virus transfers genetic material from one bacterium to another. 
  

So, the correct answer is option A.

Homeodomain is a DNA-binding domain having 60 amino acids that is present in transcription factors which regulate expression of homeotic genes, hence, the name homeodomain. These genes regulate the development of body patterns and known as homeogenes. The DNA sequence that encodes this domain is known as the homeobox.

AUG is the initiation codon. Translation starts with a chain initiation codon or start codon and terminates with a stop codon. The start codon is the first codon of a messenger RNA (mRNA) transcript translated by a ribosome. The start codon always codes for methionine in eukaryotes and a modified Met (fMet) in prokaryotes. The most common start codon is AUG.

• Termination of chain growth in protein synthesis is brought about by UAA, UAG, UGA. 
• Translation starts with a chain initiation codon or start codon and terminates with a stop codon. The three stop codons have been given names - UAG is amber, UGA is opal , and UAA is ochre. 
• Stop codons are also called "termination" or "nonsense" codons. 
• They signal the release of the nascent polypeptide from the ribosome because there is no cognate tRNA that has anticodons complementary to these stop signals, and so a release factor binds to the ribosome instead.
  Hence, the correct option is B.

Correct Option: A
Explanation:

• Translation is initiated with a chain initiation codon and terminates with a stop codon.
• The initiation codon is the first codon of a messenger RNA translated by a ribosome.
• AUG codes for methionine in eukaryotes.

Hence, AUG is an initiation codon.

Formation of mRNA from DNA is called as transcription. Transcription is when RNA is made from DNA. During transcription, RNA polymerase makes a copy of a gene from the DNA to mRNA as needed. During transcription, the DNA site at which RNA polymerase binds is called as promoter. Transcription commences with one or more sigma factor protein binds to the RNA polymerase holoenzyme, allowing it to bind to  promoter DNA. RNA polymerase creates a transcription bubble, which separates the two strands of the DNA helix. This is done by breaking the hydrogen bonds between complementary DNA nucleotides.

DNA polymerase and ligase as well as RNA polymerase and ligase have an important role in DNA replication. DNA replication, like all biological polymerization processes, proceeds in three enzymatically catalyzed and coordinated steps : initiation, elongation and termination. All enzymes mentioned play important roles in these steps of replication.

Okazaki fragments are short, newly synthesized DNA fragments that are formed on the lagging template strand during DNA replication. They are complementary to the lagging template strand, together forming short double-stranded DNA sections. On the leading strand DNA replication proceeds continuously along the DNA molecule as the parent double-stranded DNA is unwound, but on the lagging strand the new DNA is made in installments, which are later joined together by a DNA ligase enzyme.

Formation of RNA on DNA template is called as transcription. Transcription is when RNA is made from DNA. During transcription, RNA polymerase makes a copy of a gene from the DNA to mRNA as needed. During transcription, the DNA site at which RNA polymerase binds is called as promoter. Transcription commences with one or more sigma factor protein binds to the RNA polymerase holoenzyme, allowing it to bind to  promoter DNA. RNA polymerase creates a transcription bubble, which separates the two strands of the DNA helix. This is done by breaking the hydrogen bonds between complementary DNA nucleotides.

Termination of chain growth in protein synthesis is brought about by UAA, UAG, UGA. The three stop codons have been given names- UAG is amber, UGA is opal, and UAA is ochre. Stop codons are also called "termination" or "nonsense" codons. They signal release of the nascent polypeptide from the ribosome because there is no cognate tRNA that has anticodons complementary to these stop signals, and so a release factor binds to the ribosome instead.