Evolutionary theories. The Belgian George Lemaitre proposed the idea that about 20000 million years ago all the matter in the universe—enough, he estimated, to make up a hundred thousand million galaxies—was all concentrated in one small mass, which he called the "primeval atom". This primeval atom exploded for some reasons, sending its matter out in all directions, and as the expansion slowed down, a steady state resulted, at which time the galaxies formed. Something then upset the balance and the universe started expanding again, and this is the state in which the universe is now. There are variations on this theory: it may be that there was no steady state. However, basically, evolutionary theories take it that the universe was formed in one place at one point in time and has been expanding ever since.
Will the universe continue to expand It may be that the universe will continue to expand for ever, but some astronomers believe that the expansion
A. That new material is continually being formed.
B. That, in time, the universe will contract.
C. That the universe is expanding at present.
D. That "a big hang" started the expansion.
The evolutionary process culminating in man was finally completed about 35,000 years ago with the appearance of Homo Sapiens, or "thinking man." (1) in broadest perspective, this represents the second major turning (2) in the course of (3) on this planet. The first occurred when life (4) out of inorganic matter. After that momentous (5) , all living forms evolved by adapting (6) their environment, as was evident during the climate turmoil of the Pleistocene. But with the (7) of man, the evolutionary process was (8) . No longer did genes adapt to environment. Instead, man adapted by changing the environment to (9) his genes. Today, a third (10) turning point appears (11) , as man’s growing knowledge of the structure and function of genes may soon enable him to (12) his genes as well as his environment.
Man, and only man, has been able to create a made-to-order environment,
A. consists of
B. conceives of
C. combines with
D. shut out
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