The correct sequence for the formation of chemicals on the primitive earth is

• NH₃, protein, carbohydrate and nucleic acid

• NH₃, water, nucleic acids and proteins

• NH₃, nucleic acids, protein and carbohydrate

• protein, carbohydrate, water and nucleic acids

Which of the following evidences does not favour the Lamarckian concept of inheritance of acquired characters

• Absence of limbs in snakes

• Melanisation in peppered moth

• Presence of webbed toes in aquatic birds

• Lack of pigment in cave-dwelling animals

93.

Keystone species deserve protection because these

• are capable of surviving in harsh environmental conditions

• indicate presence of certain minerals in the soil

• have become rare due to overexploitation

• play an important role in supporting other species.

Assertion: Chimpanzee is the closest relative of the present day humans.

Reason: The banding pattern in some autosomes of man and chimpanzee is remarkably similar.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Assertion: Analogous organs are a result of divergent evolution.

Reason: Eye of octopus and of mammals depict divergent evolution.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

The correct sequence ofstages in the evolution of modern man (Homo sapiens), is

• Homo erectus, Australopithecus, neanderthal man, cro-magnon man, modern man

• Australopithecus, Homo erectus, neanderthal man, cro-magnon man, modern man

• Neanderthal man, Australopithecus, cromagnon man, Homo erectus, modern man

• Australopithecus, Neanderthal man, cromagnon man, Homo erectus, modern man

Which one ofthe following is reptilian ancestor of birds

• Hesperornis

• Archaeopteryx

• Ichthyornis

• Lycaenops

Assertion: Darwin's finches are a classical example of natural selection.

Reason: Darwin explained that the difference in size and shape of the beaks of the species was a result ofthe adaptation ofthe species to different food habits.

• If both assertion and reason are true and reason is the correct explanation of assertion. 

• If both assertion and reason are true but reason is not the correct explanation of assertion. 

• If assertion is true but reason is false. 

• If both assertion and reason are false.

Assertion : Hardy-Weinberg principle states that in the absence of disturbing influences, gene frequencies of large populations of sexually reproducing organisms do not change, provided that matings, occur at random.

Reason : The disturbing influences include mutation, gene flow, genetic drift, genetic recombination and natural selection.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false

In Miller's experiment, he used a mixture of CH₄, NH₃, H₂ and water vapour in a closed flask to mimic early earth conditions. What was the temperature at which this flask was kept?

• 800$°$C

• 1200$°$

• 200$°$C

• 400$°$C