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As soon as the king reached the camp and sat comfortably, the falcon, which had tolerated the pain till then, gasped and succumbed to death.

The king placed the cup in front of the falcon. The falcon overturned the cup instead of drinking from it. The king filled the cup again and placed it in front of the falcon. But, the bird upset the cup again. He filled the cup and placed it before his horse, but before the horse could drink it, the falcon hurriedly upset the cup. This made the king very angry.

The king collected the dripping liquid and placed it before the falcon twice, but it overturned the cup. It did not allow the horse to drink the liquid. The king was angry because the falcon neither drank it nor allowed the horse to drink it. So, he cut off the falcon’s wings with his sword.

The falcon knew that it was poison. It did not want to drink it. So, it upset the cup.

A) it upset the filled cup thrice

Correct Answer is  : C) gauntlet

The gazelle was trapped within the area ‘covered by the net. The hunting men started to converge on the gazelle. The gazelle moved towards the king. It suddenly jumped above the head of the king and escaped.

B) that a poisonous viper was lying up above the tree

The king’s men spread the net wide to catch the prey. A gazelle was trapped. When the hunting troop started to close in, the gazelle moved towards the king. It suddenly jumped over the king and escaped. The king started chasing the gazelle on his horse. His pet falcon flew high up in the air and spotted the running gazelle. The falcon swooped down on the gazelle and blinded it with her sharp talons. The king struck the blind gazelle with his mace and killed it.’

Correct option: (D) all of these

1. Histone octamer 

2. DNA

(a) In A, replication is continuous and form leading strand but in B replication is discontinuous and form lagging strand. 

(b) In B, short stretch of Okazaki fragments are connected with the help of DNA ligase and form continuous strand 

(c) The replication occur within a small opening of the DNA helix, referred to as replication fork. It appears as Y shaped forked structure.

(c) 3′ -> TAAGC -> 5′

1) DNA finger printing 

(2) The technique, is based on following procedure 

(i) isolation of DNA,

(ii) digestion of DNA by restriction endonucleases, 

(iii) separation of DNA fragments by electrophoresis, 

(iv) transferring (blotting) of separated DNA fragments to synthetic membranes, such as nitrocellulose or nylon,

(v) hybridisation using labelled VNTR probe, and 

(vi) detection of hybridised DNA fragments by autoradiography

Correct option: (B) Monera

In this closely associated genes function as unit called operon If lactose is present in a medium, it has to be breakdown into glucose and galactose ,for this positive control of operon works and structural genes transcribe with the help of switch on condition of operator gene. This is due to binding of RNA polymerase on promoter site of DNA.

Cytidine, All others are nitrogen bases.

a. A is Okazaki fragment. These fragments are joined by DNA ligase enzyme 

b. B is RNA primer. It provides 3’ OH to which nucleotide gets attached by ester bond.

AUG is an example of a codon having dual function.

Detailed Answer :

The codon AUG has a dual function. It functions as an initiating codon and also codes for methionine.

1. DNA regulates and controls all the cellular activities.

2. It replicates and gets distributed equally to the daughter cells when the cell divides. 

3. It is a carrier of genetic information. 

4. Heterocatalytic function : DNA directs the synthesis of chemical molecules other than itself. E.g. Synthesis of RNA (transcription), synthesis of protein (Translation), etc. 

5. Autocatalytic function : DNA directs the synthesis of DNA itself. E.g. Replication. 

6. DNA is a master molecule of a cell that initiates, guides, regulates and controls the process of protein synthesis.

Proteins serve as structural components, enzymes and hormones.

Matthew Meselson and Franklin Stahl performed the following experiment in 1958. They grew E. coli in a medium containing 15NH4C1 (15N is the heavy isotope of nitrogen) as the only nitrogen source for many generations. The result was that l5N was incorporated into newly synthesised DNA (as well as other nitrogen containing compounds).

 This heavy DNA molecule could be .distinguished from the normal DNA by centrifugation in a cesium chloride (CsCl) density gradient 15N is not a radioactive isotope, and it can be separated from 14N only based on densities).

Aminoacylation of tRNA or charging of tRNA is the activation of amino acids in the presence of ATP and their linkage to their cognate tRNA. If two such charged tRNAs are brought close enough, the formation of peptide bond between them would be favoured energetically.

In the complete absence of expression of lac operon, permease will not be synthesised which is essential for transport of lactose from medium into the cells. And if lactose cannot be transported into the cell, then it cannot act as inducer. Hence, cannot relieve the lac operon from its repressed state. Therefore, lac operon is always expressed.

AUG acts as an initiation codon and also codes for methionine.

Gel electrophoresis is used to separate DNA fragments.

SNPs—Single nucleotide polymorphisms 

BAC—Bacterial artificial chromosome 

YAC—Yeast artificial chromosome

In the complete absence of expression of lac operon, permease will not be synthesised which is essential for transport of lactose from medium into the cells. And if lactose cannot be transported into the cell, then it cannot act as inducers, hence cannot relieve the lac operon from its repressed state.

Advantages:

1.Knowledge about the effects of DNA variations among individuals can lead to revolutionary new ways to diagnose, treat and some day prevent the thousands of disorders that affect human beings.

2. Besides providing clues to understanding human biology, learning about non-human organisms DNA sequences can lead to an understanding of their natural capabilities that can be applied toward solving challenges in health care, agriculture, energy production, environmental remediation.

3. Deriving meaningful knowledge from the DNA sequences will define research through the coming decades leading to our understanding of biological systems.

4. They can study all the genes in a genome, for example, all the transcripts in a particular tissue or organ or tumor, or how tens of thousands of genes and proteins work together in interconnected networks to orchestrate the chemistry of life. 

Disadvantages:

1. It creates the problem of patenting of genes.

2. Persons becomes more careless.

Watson and Crick had the following informations which helped them to develop a model of DNA: 

i. Chargaff ’s Law suggesting A=T and C G. 

ii. Wilkins and Franklin’s X-ray diffraction studies on DNA’s physical structure. 

Based on these information, Watson and crick proposed 

i. complementary base-pairing of nitrogenous bases 

ii. semi-conservative mode of replication 

iii. occurrence of mutation through tautomerism.

Watson and Crick had the following information which helped them to develop a model of DNA.

(i)  Chargaffs’ law suggesting A = T and C = G.

(ii)  Wilkins and Rosalind Franklin’s work on DNA crystal’s X-ray diffraction studies about DNA’s physical structure.

(iii)  Watson and crick proposed

a.  How complementary bases may pair

b.  Semi conservative replication

Methylated guanosine cap helps in binding of mRNA to smaller ribosomal sub-unit during initiation of translation. Poly–A tail provides longevity to mRNA’s life. Tail length and longevity of mRNA are positively correlated.

(i) Methylated guanosine helps the mRNA for its binding with smaller subunit of ribosome during initiation of translation. 

(ii) Poly a tail provides longevity to the mRNA.

Correct answer is (c) hnRNA

DNA polymorphism in a population arise due to presence of inheritable mutations at high frequency.

DNA polymorphism is applicable in genetic mapping and DNA finger printing.

Methylated Guanine cap helps in binding of mRNA to smaller ribosomal sub-unit during initiation of translation. Poly-A tail provides longevity to mRNA’s life. Tail length and longevity of mRNA are positively correlated.

Polymorphism (variation at genetic level) arises due to mutations. Allelic sequence variation has traditionally been described as a DNA polymorphism if more than one variant (allele) at a locus occurs in human population with a frequency greater than 0.01. In simple terms, if an inheritable mutation is observed in a population at high frequency, it is referred to as DNA polymorphism. Polymorphism become very useful identification tool in forensic applications. Further, as the polymorphisms are inheritable from parents to children, DNA fingerprinting is the basis of paternity testing, in case of disputes.

Functional mRN A of structural genes need not always include all of its exons. This alternate splicing of exons is sex-specific, tissue-specific and even developmental stage-specific. By such alternate splicing of exons, a single gene may encode for several isoproteins and/or proteins of similar class. In absence of such a kind of splicing, there should have been new genes for every protein/isoprotein. Such an extravagancy has been avoided in natural phenomena by way of alternative splicing.

The defect is caused by the substitution (trans version) of Glutamic acid (Glu) by Valine (Val) at the sixth position of the betaglobin chain of the haemoglobin molecule. The substitution of amino acid in the glob in protein results due to the single base substitution at the sixth codon of the betaglobin gene from GAG to GUG. The mutant haemoglobin molecule undergoes polymerisation under low oxygen tension causing the change in the shape of the RBC from biconcave disc to elongated sickle like structure. Sickle-shaped red blood cells that obstruct capillaries and restrict blood flow to an organ resulting in ischaemia, pain, necrosis, and often organ damage.

Tandemness in repeats provides many copies of the sequence for fingerprinting and variability in nitrogen base sequence in them. Being individual-specific, this proves to be useful in the process of DNA fingerprinting.

Tandemness in repeats provides many copies of the sequence for fingerprinting, and variability in nitrogen base sequence in them. Being individual-specific, this proves to be useful in the process of DNA fingerprinting.

b. The center of flocs will become anoxic, which would cause death of bacteria and eventually breakage of flocs.

(c) fusion of three haploid nuclei

(d) all the above

(d) all the above

(b) Lactate fermentation

c. Indian Agricultural Research Institute and Khadi & Village Industries Commission