At which stage of HIV infection does one usually show symptoms of AIDS?

• Within 15 days of sexual contact with an infected person

• When the infected retro virus enters host cells

• When HIV damages large number of helper T-Lymphocytes

• When HIV damages large number of helper T-Lymphocytes

A man whose father was colour blind marries a woman, who had a colourblind mother and normal father. What percentage of male children of this couple will be colourblind.

• 25%

• 0%

• 50%

• 50%

Select the correct option.

• Direction of RNA Synthesis	Direction of reading of the template DNA strand
  5’-3’	3’-5’

• Direction of RNA Synthesis	Direction of reading of the template DNA strand
  3’-5'	5’-3'

• Direction of RNA Synthesis	Direction of reading of the template DNA strand
  5’-3’	5’-3'

• Direction of RNA Synthesis	Direction of reading of the template DNA strand
  5’-3’	5’-3'

If 20 J of energy is trapped at the producer level, then how much energy will be available to peacock as food in the following chain?

Plant--> Mice --> Snake --> Peacock

• 0.02 J

• 0.002 J 

• 0.2 J 

• 0.2 J 

Given below is a simplified model of phosphorus cycling in a terrestrial ecosystem with four blanks (A-D). Identify the blanks.

• A	B	C	D
  Rock Minerals	Detritus	Litter fall	Producers

• A	B	C	D
  Litter fall	Producers	Rock minerals	Detritus

• A	B	C	D
  Detritus	Rock minerals	Producer	Litter fall

• A	B	C	D
  Detritus	Rock minerals	Producer	Litter fall

Just as a person moving from Delhi to Shimla to escape the heat for the duration of hot summer, thousand of migratory birds from Siberia and other extremely cold Northern regions move to

• Western Ghat

• Meghalaya

• Corbett National Park

• Corbett National Park

A scrubber in the exhaust of a chemical industrial plant removes

• Gases like sulphur dioxide

• Particulate matter of the size 5 micrometre or above

• Gases like ozone and methane

• Gases like ozone and methane

Given below is the representation of the extent of global diversity of invertebrates. What groups the four portions (A - D) represent respectively?

• A	B	C	D
  Insects	Crustaceans	other animal group	Molluscs

• A	B	C	D
  Crustacean	Insects	Molluscs	other animal groups

• A	B	C	D
  Molluscs	Other animal groups	Crustaceans	Insects

• A	B	C	D
  Molluscs	Other animal groups	Crustaceans	Insects

Which is the particular type of drug that is obtained from the plant whose one flowering branch is shown below?

• Hallucinogen

• Depressant

• Stimulant

• Stimulant

What gases are produced in anaerobic sludge digesters?

• Methane and CO₂ only

• Methane hydrogen sulphide and CO₂

• Methane, hydrogen sulphide and O₂

• Methane, hydrogen sulphide and O₂