Assertion: An organism with lethal mutation may not even develop beyond the zygote stage.
Reason: All types of gene mutations are lethal.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false.
Which one of the following pairs is correctly matched with regard to the codon and the amino acid coded by it
UUA - valine
AUG - cysteine
AAA - lysine
CCC - alanine
Assertion : Replication and transcription occur in the nucleus but translation occurs in the cytoplasm.
Reason : mRNA is transferred from the nucleus into the cytoplasm where ribosomes and amino acids are available for protein synthesis.
If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion
If both Assertion and Reason are true but the Reason is not the correct explanation of the assertion
If Assertion is true but Reason is false
If both Assertion and Reason are false
Which one of the following pairs of terms/ names mean one and the same thing?
Gene pool - genome
Codon - gene
Cistron - triplet
DNA fingerprinting - DNA profiling
What is true about tRNA?
It binds with an amino acid at it 3' end
It has five double stranded regions
It has a codon at one end which recognizes the anticodon on messenger RNA
It looks like clover leafin the three dimensional structure
All eukaryotic genes contain two kinds of base sequences. Which of the following plays role in protein synthesis ?
Introns
Exons
Electrons
Both (a) and (b)
The direction of DNA replication is from :
amino acid end
3' end towards 5' end
5' end towards 3' end
amino terminus to carboxy terminus
In operon concept, regulator gene functions as:
repressor
regulator
inhibitor
initiator
A.
repressor
Operon is defined as a set of genes transcribed under the control of an operator gene. It is a segment of DNA containing adjacent genes including structural genes, an operator gene, and a regulatory gene. An operon is thus a functional unit of transcription and genetic regulation. In operon model, regulator gene directs the synthesis of proteins. It may be an active repressor or an inactive repressor.