Question About The passage is primarily concerned with:

the possibility of life on Mars

selecting sites for landers on Mars

findings of Christopher McKay on Mars

Question About Which of the following statements is not true?

If any bacteria are alive today on Mars, they must have survived from the time before the planet cooled.

Space photographs of Martian craters should reveal to the explorers signs of life there.

Bacteria frozen into permafrost at the Martian South Pole may be viable.

On digging up, more than 3 million years old Siberian permafrost has revealed bacteria.

Algae could have existed on Mars.

Comprehension

If life exists on Mars, it is most likely to be in the form of bacteria buried deep in the planet's permafrost or lichens growing within rocks, say scientists from NASA. There might even be fossilized Martian algae locked up in ancient lake beds, waiting to be found. Christopher McKay of NASA's Ames Research Centre in California told the AAAS that astrobiologists, who look for life on other planets, should look for clues among the life forms of the Earth's ultra-cold regions, where conditions are similar to those on Mars. Lichens, for example, are found within some Antarctic rocks, just beneath the surface where sunlight can still reach them. The rock protects the lichen from cold and absorbs water providing enough for the lichen's needs, said McKay. Bacteria have also been found in 3-million-year-old permafrost dug up from Siberia. If there are any bacteria alive on Mars today, they would have had to have survived from the time before the planet cooled more than 3 billion years ago. Nevertheless, McKay is optimistic: ``It may be possible that bacteria frozen into the permafrost at the Martian South Pole may be viable.'' McKay said algae is found in Antarctic lakes with permanently frozen surfaces. Although no lakes are thought to exist on Mars today, they might have existed long ago. If so, the dried-out Martian lake beds may contain the fossilised remains of algae. On Earth, masses of microscopic algae form large, layered structures known as Stromatolites, which survive as fossil on lake beds, and the putative Martian algae might have done the same thing, said Jack Farmer, one of McKay's colleagues. The researchers are compiling a list of promising Martian lake beds to be photographed from spacecraft, said Farmer. Those photographs could help to select sites for landers that would search for signs of life, past or present. ``If we find algae on Mars, I would say the Universe is lousy with algae,'' McKay said. ``Intelligence would be another question.''

Question: 1

The passage is primarily concerned with:

Updated On: Apr 14, 2026

the possibility of life on Mars
selecting sites for landers on Mars
research on Mars
findings of Christopher McKay on Mars
algae found on Mars

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The Correct Option is A

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Question: 2

The most primitive forms of life likely to exist on Mars are all the following except

Updated On: Apr 14, 2026

Virus and space
Bacteria
Lichen
Algae
Microbes

Show Solution

The Correct Option is A

Solution and Explanation

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Question: 3

Which of the following statements is not true?

Updated On: Apr 14, 2026

If any bacteria are alive today on Mars, they must have survived from the time before the planet cooled.
Space photographs of Martian craters should reveal to the explorers signs of life there.
Bacteria frozen into permafrost at the Martian South Pole may be viable.
On digging up, more than 3 million years old Siberian permafrost has revealed bacteria.
Algae could have existed on Mars.