An example of inverted ecological pyramid is:

Observe the figure and answer the following:


What is represented by figure D?

ELISA is based on the principles of:

Identify the correct sequence of trophic levels in a food-chain.
(A) Man
(B) Phytoplankton
(C) Fishes
(D) Zooplankton
Choose the correct answer from the options given below:

Which one among the following contraceptive, inhibits ovulation and implantation of female reproductive system?

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 or chemicals can not quickly reduce the symptoms of allergy?

Which one of the following is an example of man-made ecosystem?

If the product of matrices \(\left[\begin{array}{cc}\cos ^2 \theta & \cos \theta \sin \theta \\ \cos \theta \sin \theta & \sin ^2 \theta\end{array}\right]\) and \(\left[\begin{array}{cc}\cos ^2 \beta & \cos \beta \sin \beta \\ \cos \beta \sin \beta & \sin ^2 \beta\end{array}\right]\) is a null matrix, then \(\theta\) and \(\beta\) differ by:

The function \(f(x)=x^3-3 x\) is :

In the electromagnetic spectrum, the visible spectrum lies between :

If \(z=3 x+4 y\) be the objective function of a linear programming problem (LPP) and (3,1), (2,4), (0,4), (5,0) be corner points of the bounded feasible region. Then the maximum value of objective function is

Nitriles on reduction with lithium aluminum hydride produce

A charged particle carrying charge \(q = 1 \mu C\) moves in a uniform magnetic field with velocity \(v_1 = 10^6 \text{ m/s}\) at an angle of \(45^\circ\) with the x-axis in the xy-plane and experiences a force \(F_1 = 0.4\sqrt{2} \text{ N}\) along the negative z-axis. When the same particle moves with velocity \(v_2 = 10^6 \text{ m/s}\) along the z-axis, it experiences a force \(F_2\) in the y-direction. Find the magnitude of the magnetic field.