Three environmental problems of the Sunderbans are- imbalance in the numbers of prey and predators destruction of mangrove plants due to urbanisation rising sea level Analyse the probable effects of the three problems. Mention the location and the name of one endangered species of a biodiversity hotspot distributed in and outside the geographical area of India. [3+2=5] OR Describe the nitrogen cycle with the help of a word diagram. Analyse any two problems which may arise if the nitrogen cycle is disturbed. [3+2=5]

Explain the following three problems related to ever-increasing human population- Over-exploitation and depletion of natural resourcese Changes in atmospheric condition and global warming Deforestation and loss of ecosystems Two major causes behind the loss of biodiversity are over-exploitation and destruction of habitat due to change in land use pattern - establish the validity of the statement with proper example. [3+2=5] Or What might be the reasons behind the disturbances in Nitrogen Cycle ? It is very much essential to publish a PBR document for each village of India — which information can be gathered from a PBR regarding biodiversity ? [3+2=5]

Among nitrobacter, rhizobium, nitrosomonas, nitrite bacteria, pseudomonas — which one is found in the fourth phase of the nitrogen cycle? (a) Rhizobium (b) Nitrosomonas (c) Nitrobacter (d) Pseudomonas

Which biogas is not produced by the decomposition of dung and dead plants? (a) CH₄ (b) NH₃ (c) H₂S (d) H₂

With which step of Nitrogen Cycle microbes like Nitrosomonas and Nitrobacter are associated? (a) Nitrification (b) Denitrification (c) Nitrogen fixation (d) Ammonification

Which environmental problems arise if nitrogen cycle is hampered?

Which of the following are the refractive media of the eye? (a) Cornea, aqueous humour, lens, vitreous humour (b) Retina, aqueous humour, lens, vitreous humour (c) Cornea, retina, lens, iris (d) Aqueous humour, iris, vitreous humour, cornea

In which of the following crosses, will the F1 generation seed's tall and dwarf traits appear in a 1:1 ratio? (a) Tt x Tt (b) TT x Tt (c) TT x tt (d) Tt x tt

What will be the phenotypic ratio of progeny obtained from the hybridization between YyRR and YYrr genotypes? (a) 2:1 (b) 1:2 (c) 2:2 (d) 1:4

If a population undergoes three generations, and if each generation consists of only males, what is the probability that females will be present in the fourth generation? (a) 100% (b) 0% (c) 50% (d) 75%

Choose the odd word and write it: Hypothalamus, Pons, Medulla Oblongata, Cerebellum

It is homozygous dominant in one locus and heterozygous dominant in the other locus – example of such genotype is BBrr.