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Heredity studies the genetic mechanisms through which specific traits, characteristics, and variations are passed down from parents to their offspring.
Correct Answer:
(B) Mapping of genes
Gene mapping is the method used for determining the location of gene and relative distances between genes on a chromosome. The essence of all genome mapping is to place a collection of molecular markers onto their respective positions on the genome. Molecular markers come in all forms. Genes can be viewed as one special type of genetic markers in the construction of genome maps and mapped the same way as any other markers.
Ques: 2
The characteristics features of genetic code are:
It is always universal
It is triplet of nucleotides bases corresponding to 20 amino acids
It is non-overlapping, non-ambiguous and comma-less.
It has start and stop codon
Which of the statements given above are true?
Correct Answer:
(D)
All of the above
The genetic code is the set of rules used by living cells to translate information encoded within genetic material (DNA or mRNA sequences of nucleotide triplets, or codons) into proteins. In other words, the genetic code may be defined as the exact sequence of DNA (or mRNA) nucleotides read as three letter words or codons, that determines the sequence of amino acids in protein synthesis. There are 64 codons which correspond to 20 amino acids and to signals for the initiation and termination of transcription. Each triplet (codon) specifies one amino acid in a protein structure or a start signal or stop signal in protein synthesis. With three exceptions, each codon encodes for one of the 20 amino acids used in the synthesis of proteins. There are 61 sense codons in the genetic code which code for 20 amino acids. Those codons that code for signals during protein synthesis are known as signal (start and stop) codons. There are four codons which code for signal. These are AUG (start codon), UAA, UAG and UGA (stop codons). AUG codon also codes for the amino acid methionine. The genetic code is always universal, comma-less, non-overlapping, non-ambiguous and redundant.
Ques: 3
Change in the base sequence within a gene is called:
Correct Answer:
(A) Mutation
A gene is the basic physical and functional unit of heredity. Change in the base sequence within a gene is called mutation. Mutation is the changing of the structure of a gene, resulting in a variant form that may be transmitted to the subsequent generations. Mutation is the ultimate source of all genetic variation, providing the raw material on which evolutionary forces such as natural selection can act.
Ques: 4
Which of the following features of DNA makes it uniquely suited to store and transmit genetic information from generation to generation?
Correct Answer:
(A) Complementarity of the two strands
Ques: 5
Who first outlined the structure of the gene molecule (D.N.A.)?
Correct Answer:
(C) Dr. James Watson and Dr. Francis Crick
James Dewey Watson (born April 6, 1928) was an American molecular biologist, geneticist and zoologist, best known as one of the co-discoverers of the structure (double helix model) of DNA in 1953 with Francis Crick. Watson, Crick, and Maurice Wilkins were awarded the 1962 Nobel Prize in Physiology or Medicine for their discoveries concerning the "molecular structure of nucleic acids and its significance for information transfer in living material".