Read the given passage and answer the following questions:
Secondary treatment or biological treatment: The primary effluent is passed into large tanks where air is pumped into it. This allows vigorous growth of aerobic microbes. While growing, these microbes consume the major part of the organic matter in the effluent. This significantly change the BOD (biochemical oxygen demand) of the effluent. The effluent in then passed into a tank a small part of the sludge is pumped back into the aeration tank to serve as the inoculum. The remaining major part of the sludge is pumped into large tanks called sludge digesters. Here, other kinds of bacteria grow anaerobically in the sludge. The biogas produced can be used source of energy as it is inflammable. The effluent from the secondary treatment plant is generally released into natural water bodies like rivers and streams.
The anaerobic sludge digester

Match List I with List II.

List I (Example)	List II (Name of Interaction)
A. Sea anemone and clown fish	I. Competition
B. Lichens	II. Commensalism
C. Lice and Human	III. Mutualism
D. Flamingoes and resident fishes in South American lakes	IV. Parasitism

Choose the correct answer from the options given below:

Which one of the mentioned characters does not represent the true breeding line?

There are two kinds of nucleases - exonucleases and endonucleases. Exonucleases remove nucleotides from the ends of the DNA whereas, endonucleases make cuts at specific positions within the DNA. The cutting of DNA by restriction endonucleases results in the fragments of DNA. These fragments can be separated by a technique known as gel electrophoresis. Since DNA fragments are negatively charged molecules they can be separated by forcing them to move towards the anode under an electric field through a medium/matrix. Small volume cultures cannot yield appreciable quantities of products. To produce in large quantities, the development of bioreactors, where large volumes (100 - 1000 litres) of culture can be processed, was required. Thus, bioreactors can be thought of as vessels in which raw materials are biologically converted into specific products, individual enzymes, etc., using microbial plant, animal or human cells. PCR stands for Polymerase Chain Reaction. In this reaction, multiple copies of the gene (or DNA) of interest are synthesised in vitro using two sets of primers (small chemically synthesised oligonucleotides that are complementary to the regions of DNA) and the enzyme DNA polymerase.
Which one of the following enzymes remove nucleotides from the ends of the DNA?

Read the passage carefully and give the answers to the question :
Does the number of species in a community really matter to the functioning of the ecosystem? This is a question for which ecologists have not been able to give a definitive answer. For many decades, ecologists believed that communities with more species, generally, tend to be more stable than those with less species. According to the International Union for Conservation of Nature and Natural Resources (IUCN) (2004), the total number of plant and animal species described so far is more than 1.5 million.
The following are the various hypotheses proposed in explaining the greatest biological diversity in tropics except :

Observe the diagram and answer the following questions:

Identify the correct statements with respect to retrovirus.
A. DNA genome of the virus forms complementary RNA
B. After getting into the body of a person the virus enter into macrophages
C. The viral RNA gets incorporated into host cell DNA
D. The macrophages act like virus factory
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Which of the following statements regarding primary treatment of sewage water are correct:
A. It is a physical treatment
B. It is based on formation of flocs to trap the particulate matter from the sewage
C. It removes large and small particles through filtration and sedimentation.
D. It removes floating debris by filtration and grit by sedimentation

Select the correct statements from the following :
(A) EDTA is used in the treatment of lead poisoning
(B) vitamin B 12 is a coordination complex of Co
(C) chlorophyll is a coordination complex of Fe
(D) Wilkinson catalyst is a rhodium complex used for hydrogenation of alkenes
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The line of sight distance for two antennas of height 100 m and 400 m above earth surface is approximately: (Given \( R = 6400 \text{ km}, \sqrt{20} = 4.5 \))

Which of the following reagents convert an alcohol into an alkyl chloride?
(A) Conc. Hydrogen Chloride
(B) Phosphorus trichloride
(C) Phosphorus pentachloride
(D) Thionyl Chloride
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Let \(R\) be a relation on the set of integers given by \((x, y) \in R \Longleftrightarrow|x-y| \leq 1\). Then \(R\) is
(A) Reflexive relation
(B) Symmetric relation
(C) Transitive relation
(D) \(R\) is not a function
(E) Empty relation
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Amalgam of mercury with sodium belongs to which solute-solvent combination

Which one of the followings is not a transgenic animal?