Antibody molecule is made up of four peptide chain called as light and heavy chain are joined together by :

Which one of the followings is not a common mechanical barrier method for birth control?

Read the following passage carefully and answer the given questions.
Plasmodium, a tiny protozoan is responsible for the disease malaria. Different species of Plasmodium (P. vivax, P. malaria and P. falciparum) are responsible for different types of malaria. Of these, malignant malaria caused by Plasmodium falciparum is the most serious one and can even be fatal. Innate immunity consist of four types of barriers. These are – (i) Physical barriers- skin on our body is the main barrier which prevents entry of the micro-organisms. (ii) Physiological barriers- Acid in the stomach, saliva in the mouth, tears from eyes-all prevent microbial growth. (iii) Cellular barriers- Certain types of leukocytes (WBC) of our body like polymorpho-nuclear leukocytes (PMNL-neutrophils) and monocytes and natural killer (type of lymphocytes) in the blood as well as macrophages in tissues can phagocytose and destroy microbes. (iv) Cytokine barriers- virus-infected cells secrete proteins called interferons which protect non-infected cells from further viral infection. Allergy is due to the release of chemicals like histamine and serotonin from the mast cells. The use of drugs like anti-histamine, adrenalin and steroids quickly reduce the symptoms of allergy. Drugs like barbiturates, amphetamines, benzodiazepines, and other similar drugs, that are normally used as medicines to help patients cope with mental illnesses like depression and insomnia, are often abused.
Which one of the following drugs is not used as medicine to help patients cope with mental illnesses like depression and insomnia?

The steps of DNA fingerprinting are given below. Arrange them in a correct sequence.
(A) Separation of DNA fragments by electrophoresis
(B) Hybridisation using labelled VNTR probe
(C) Isolation and digestion of DNA
(D) Detection of hybridised DNA fragments by autoradiography
(E) Transferring of separated DNA fragments to synthetic membranes
Choose the correct answer from the options given below :

Identify the features developed by flowering plants to discourage self-pollination:
(A) Self incompatibility
(B) Synchronized pollen release and stigma receptivity
(C) Different positions of anther and stigma in a flower
(D) Producing bisexual flowers
Choose the correct answer from the options given below:

Read the following paragraph and answer the given questions.
Repeated amplification is achieved by the use of a thermostable DNA polymerase (isolated from a bacterium, Thermusaquaticus}), which remain active during the high temperature induced denaturation of double stranded DNA. The separated DNA fragments can be visualised only after staining the DNA with a compound known as ethidium bromide followed by exposure to UV radiation. The separated bands of DNA are cut out from the agarose gel and extracted from the gel piece. The convention for naming these enzymes is the first letter of the name comes from the genus and the second two letters come from the species of the prokaryotic cell from which they were isolated, e.g., EcoRI comes from Escherichiacoli} RY 13. In EcoRI, the letter 'R' is derived from the name of strain. Roman numbers following the names indicate the order in which the enzymes were isolated from that strain of bacteria. Stanley Cohen and Herbert Boyer accomplished this in 1972 by isolating the antibiotic resistance gene by cutting out a piece of DNA from a plasmid which was responsible for conferring antibiotic resistance. Since the DNA is enclosed within the membranes, we have to break the cell open to release DNA, RNA, protein, polysaccharides etc. The RNA can be removed by treatment with ribonuclease whereas proteins can be removed by treatment with protease. Other molecules can be removed by appropriate treatments and purified DNA ultimately precipitates out after the addition of chilled ethanol.

In the isolation process of genetic material, the purified DNA can be precipitated out after the addition of:

Read the passage carefully and give the answers to the question :
India was amongst the first countries in the world to initiate action plans and programmes at a national level to attain total reproductive health as a social goal.
These programmes called 'family planning' were initiated in 1951 and were periodically assessed over the past decades. Improved programmes covering wider reproduction-related areas are currently in operation. Creating awareness among the people about various reproduction-related aspects and providing facilities and support for building up a reproductively healthy society are the major tasks under these programmes.
Which of the following statements is incorrect with respect to Medical Termination of Pregnancy?

Ammonia is manufactured by:
\(N _2(g)+3 H _2(g) \rightleftharpoons 2 NH _3(g) \quad \Delta H=-46.1 kJ / mol\)
The various steps involved are:
(A) Condensation of mixture of gases
(B) Passing the gaseous mixture over catalyst
(C) Compression of the mixture of gases
(D) Recirculation of the gaseous mixture
Choose the correct answer from the options given below :

Introduction of which of the following on Galopagos islands caused extinction of Abingdon tortoise ?

Match List-I with List-II

List-I ( Matrix A )	List-II ( Determinant of adj A )
(A) \(\left[\begin{array}{cc}2 & 1 \\0 & -1\end{array}\right]\)	(I) 6
(B) \(\left[\begin{array}{cc}0 & 1 \\4 & -1\end{array}\right]\)	(II) 5
(C) \(\left[\begin{array}{cc}1 & 2 \\-3 & -1\end{array}\right]\)	(III) \(-4\)
(D) \(\left[\begin{array}{cc}4 & -2 \\3 & 0\end{array}\right]\)	(IV) \(-2\)

Choose the correct answer from the options given below :

Eight charges having values as shown in figure are arranged symmetrically on a circle of radius 10 cm in air. The potential at the centre O is

The function \(f(x)=\left\{\begin{array}{ll}\frac{x^2+2 x-3}{x-1}, & \text { if } x \neq 1 \\ 0, & \text { if } x=1\end{array}\right.\) is

The interval in which \(y=x^2 e^{-x}\) is strictly increasing is: