In sewage treatment, flocs are:

Microbes in human welfare Microbes are a very important component of life on earth. we use microbes and microbially derived products almost every day, like LAB to make curd, yeast to make bread, adding flavor and texture to cheese, producing antibiotics etc. The addition of LAB, improves the milk quality by increasing vit. B12. Cheese is one of the oldest food items in which microbes are used. For example, large holes in Swiss cheese are due to CO2 produced by the bacterium Propionibacterium sharmanii. The BOD test measures the rate of uptake of oxygen by microorganisms in a sample of water and thus, indirectly, BOD is a measure of the organic matter present in the water. The greater the BOD of waste water, the more is its polluting potential. In anaerobic sludge digesters, bacteria produce a mixture of gases like methane, hydrogen sulphide and carbon dioxide. These gases form biogas and can be used as a source of energy. Biofertilisers are organisms that enrich the nutrient quality of the soil. The main sources of biofertilisers are bacteria, fungi and cyanobacteria. You have studied about the nodules on the roots of leguminous plants formed by the symbiotic association of Rhizobium. These bacteria fix atmospheric nitrogen into organic forms, which is used by the plant as a nutrient. Other bacteria can fix atmospheric nitrogen while free-living in the soil (examples Azospirillum and Azotobacter).
Which statement is true about LAB ?

In flowering plants, double fertilization results in the formation of:

If 50000 J energy available to primary producer, then energy available to tertiary consumer will be:

Match List I with List II.

LIST I	LIST II
A. Endemism	I. Ex-situ conservation
B. Alien species	II. Variations in Rauwolfia vomitoriea
C. Cryopreservation	III. Species confined to a particular region
D. Genetic diversity	IV. Parthenium

Choose the correct answer from the options given below:

Read the following passage carefully and answer the given questions.
Bioactive molecule, cyclosporin A, that is used as an immunosuppressive agent in organ-transplant patients, is produced by the fungus Trichoderma polysporum. Statins produced by the yeast Monascus purpureus have been commercialised as blood-cholesterol lowering agents. It acts by competitively inhibiting the enzyme responsible for synthesis of cholesterol. Baculoviruses are pathogens that attack insects and other arthropods. The majority of baculoviruses used as biological control agents are in the genus Nucleopolyhedrovirus. These viruses are excellent candidates for species-specific, narrow spectrum insecticidal applications. They have been shown to have no negative impacts on plants, mammals, birds, fish or even on non-target insects. BOD refers to the amount of the oxygen that would be consumed if all the organic matter in one liter of water were oxidised by bacteria. The sewage water is treated till the BOD is reduced. Cheese, is one of the oldest food items in which microbes were used. Different varieties of cheese are known by their characteristic texture, flavour and taste. For example, the large holes in 'Swiss cheese' are due to production of a large amount of CO₂ by a bacterium named Propionibacterium sharmanii.
Statins are produced by:

The size of VNTR varies from:

Match List-I with List-II

List-I	List-II
(A) \(\int \frac{d x}{x^2-16}\)	(I) \(\frac{1}{8} \log \left|\frac{4+x}{4-x}\right|+c\)
(B) \(\int \frac{d x}{x^2+16}\)	(II) \(\log \left|x+\sqrt{x^2-16}\right|+c\)
(C) \(\int \frac{d x}{16-x^2}\)	(III) \(\frac{1}{8} \log \left|\frac{x-4}{x+4}\right|+c\)
(D) \(\int \frac{d x}{\sqrt{x^2-16}}\)	(IV) \(\frac{1}{4} \tan ^{-1}\left(\frac{x}{4}\right)+c\)

Choose the Correct answer from the options given below :

Which of the following are the properties of photons?
(A) The rest mass of a photon is zero
(B) Each photon has a definite energy and an indefinite linear momentum
(C) A photon may collide with a material particle and the total energy and the total momentum remain conserved in such a collision
(D) Photons are deflected by electric and magnetic fields
Choose the correct answer from the options given below

At a place the angle of dip is \( 30^{\circ} \). If the horizontal component of the earth's magnetic field is \( B_H \), the total magnetic field of the earth will be :

Identify the correct statements
(A) Electric current arises due to the continuous flow of electrons or ions.
(B) A current flows through a conductor only when there is an electric field within the
conductor.
(C) The drift velocity of electrons is directly proportional to the applied electric field.
(D) The average thermal velocity of the electrons in a conductor is zero.
(E) In the absence of an electric field, the electrons in a conductor are at rest.
Choose the correct answer from the options given below :

The refractive index of an equilateral prism is \( \sqrt{3} \). The angle of incidence for which angle of deviation is minimum is :

In the given equations (Note: equations are not balanced):
\(Zn + Conc. HNO_3 \rightarrow Zn(NO_3)_2 + x + H_2O\)
\(Zn + Dil. HNO_3 \rightarrow Zn(NO_3)_2 + y + H_2O\)
The compounds \(x\) and \(y\) respectively are: