Choose the correct statements about the origin of life from the following:
A. Analysis of meteorite content revealed compounds similar to those formed in Miller’s experiment.
B. The first non-cellular forms of life could have been giant molecules such as RNA, protein and polysaccharides.
C. The first cellular forms of life were probably multicellular.
D. The first cellular forms of life lived on land.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → A and B only
After chemical evolution, giant molecules appeared, and much later the first cells. NCERT describes what these early forms were like and where they lived.
A. Analysis of meteorite content revealed compounds similar to those formed in Miller’s experiment. — True. Such compounds in meteorites suggest that similar processes are taking place elsewhere in space.
B. The first non-cellular forms of life could have been giant molecules such as RNA, protein and polysaccharides. — True. These first non-cellular forms could have arisen about 3 billion years back, and these capsules perhaps reproduced their molecules.
C. The first cellular forms of life were probably multicellular. — False. The first cellular forms were probably single-cells. Multicellular forms came later.
D. The first cellular forms of life lived on land. — False. All life forms were then in a water environment only. Plants were the first to invade land, much later.
So only A and B are correct.
NCERT Extract:
Origin of Life – “… He observed formation of amino acids. In similar experiments others observed, formation of sugars, nitrogen bases, pigment and fats. Analysis of meteorite content also revealed similar compounds indicating that similar processes are occurring elsewhere in space.”
Origin of Life – “… The first non-cellular forms of life could have originated 3 billion years back. They would have been giant molecules (RNA, Protein, Polysaccharides, etc.). These capsules reproduced their molecules perhaps. The first cellular form of life did not possibly originate till about 2000 million years ago. These were probably single-cells. All life forms were in water environment only.”