We should not allow mosquitoes to breed in our surroundings because they

Exine of pollen grains has prominent apertures where sporopollenin is absent are known as:

Which one of the following statement is incorrect about ecological pyramids?

Read the following paragraph carefully and answer the given questions.
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. For determining the cause of allergy, the patient is exposed to or injected with very small doses of possible allergens, and the reactions studied. The use of drugs like anti-histamine, adrenalin and steroids quickly reduce the symptoms of allergy. Heroin, commonly called smack is chemically diacetylmorphine which is a white, odourless, bitter crystalline compound. This is obtained by acetylation of morphine. Techniques like radiography (use of X-rays), CT (computed tomography) and MRI (magnetic resonance imaging) are very useful to
detect cancers of the internal organs. 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.
Which of the following cells are involved in phagocytosis and destruction of microbes?

Arrange the events of dicot embryo development in the correct sequence:
(A) Formation of heart-shaped embryo
(B) Formation of mature dicot embryo
(C) Formation of zygote
(D) Formation of globular embryo

Match List - I with List - II.

List - I	List - II
(A) Cyclosporin A	(I) Lowers blood cholesterol
(B) Streptokinase	(II) Citric acid
(C) Aspergillus niger	(III) Immunosuppressant
(D) Statin	(IV) Clot buster

Choose the correct answer from the options given below :

Identify the microbes producing commercially important organic acids and enzymes from the given options:
(A) Trichoderma polysporum
(B) Streptococcus
(C) Clostridium butylicum
(D) Aspergillus niger
Choose the correct answer from the options given below:

A thin convex lens of refractive index 1.5 has focal length f1. When immersed in a liquid of refractive index 5/3, its focal length is found to be f2. The relationship between f1 and f2 is:

The amine which will not undergo benzoylation in alkaline medium is

Which was the first discovered antibiotic ?

Read the given paragraph and answer the question:
Humans have 23 pairs of chromosomes. 22 pairs are exactly same in both males and females; these are the autosomes. A pair of X-chromosome are present in the female, whereas the presence of an X and Y chromosome are determinant of the male characteristic.
A number of disorders in human beings have been found to be associated with the inheritance of changed or altered genes or chromosomes. Broadly, genetic disorder may be grouped into two categories-Mendelian disorders and Chromosomal disorders
Which of the following is an example of a sex linked disease?

The maximum value of Z = 3x + y subject to the constraints
x + y \(\le\) 7,
x \(\le\) 5,
y \(\le\) 4,
x \(\ge\) 0, y \(\ge\) 0 is:

Arrange the following steps of gel electrophoresis in correct sequence:
(A) Staining the DNA with ethidium bromide
(B) Movement of DNA fragments towards anode under an electric field through agarose
(C) Exposure to UV radiation
(D) Separation of DNA fragments according to their size
Choose the correct answer from the options given below: