During allergic reactions, which of the following are secreted?
(A) Histamines
(B) Interferons
(C) Serotonin
(D) Pyrogens
Choose the correct answer from the options given below:

Which of the following are correct with reference to rDNA technology?
(A) Exo-nuclease removes nucleotides from the ends of DNA
(B) Replication starts at ori
(C) High velocity microparticle of gold, coated with DNA, are used to transfer DNA in a method known as gene gun
(D) Endo-nuclease makes cut at specific positions within DNA
Choose the correct answer from the options given below:

Which one of the following layers of microsporangium nourishes the developing pollen grains?

Match List I with List II

LIST I (Name of interaction)	LIST II ('o' represents neutral, '+'represents benificial, '-'represents detrimental)
A. Commensalism	I. -,-
B. Competition	II. +,+
C. Mutualism	III. -,0
D. Amensalism	IV. +,0

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The first instance of construction of an artificial recombinant DNA molecule was carried out on the plasmid of:

Given below are the names of some recent animal extinctions along with the country to which it belongs.
Match the animal with its country.

List - I (Name of extinct Animal)	List - II (Name of the country)
(A) Steller's Sea Cow	(i) Mauritius
(B) Dodo	(ii) Africa
(C) Thylacine	(iii) Russia
(D) Quagga	(iv) Australia

Choose the correct answer from the options given below :

Which one of the following sex determination systems is found in honey
bee?

Magnetic moment values for \([\text{Fe}(\text{H}_2\text{O})_6]^{3+}\) and \([\text{Fe}(\text{CN})_6]^{3-}\) are

Read the passage carefully. Attempt the questions.
An overwhelming majority (99 per cent) of animals and nearly all plants cannot maintain a constant internal environment. Their body temperature changes with the ambient temperature. In aquatic animals, the osmotic concentration of the body fluids change with that of the ambient air and water osmotic concentration. These animals and plants are simply conformers. Considering the benefits of a constant internal environment to the organism, we must ask why these conformers had not evolved to become regulators. Recall the human analogy we used above; much as they like, how many people can really afford an air conditioner? Many simply 'sweat it out' and resign themselves to suboptimal performance in hot summer months. Very small animals are rarely found in polar regions. During the course of evolution, the costs and benefits of maintainin a constant internal environment are taken into consideration. Some species have evolved the ability to regulate, but only over a limited range of environmental conditions, beyond which they simply conform.
If the stressful external conditions are localised or remain only for a short duration, the organism has five other alternatives for survival.
Identify the statements which support the reason why small animals are rarely found in polar regions.
A. Small animals have larger surface area relative to their volume
B. Small animals have larger volume relative to their surface area
C. Shrews and humming birds are not found in polar region
D. Small animals have smaller surface area relative to their volume

Hole is-

Conservation of threatened animals and plants in a special setting where they can be protected and given special care is known as:

The correct statement (s) for cubic close packed (ccp) three dimensional structure are :
(A) The number of the neighbours of an atom present in the top most layer is 12.
(B) The efficiency of atom packing is \(74\%\).
(C) The number of octahedral and tetrahedral voids per atom are 1 & 2, respectively.
(D) The unit cell edge length is \(2\sqrt{2}\) times the radius of the atom.
(E) The metals like Be, Cd, Mg, Zn have cubic close packed (ccp) structure.
Choose the correct answer from the options given below :

If \(\left[\begin{array}{cc}2 & 3 \\ 5 & 7\end{array}\right]\left[\begin{array}{cc}1 & -3 \\ -2 & 4\end{array}\right]=\left[\begin{array}{cc}-4 & 6 \\ -9 & x\end{array}\right]\), then the value of \(x\) is: