I: | The earliest organisms that appeared on the earth were non-green and presumably anaerobes. |
II: | The first autotrophic organisms were the chemoautotrophs that never released oxygen. |
Which of the following is the correct sequence of events in the origin of life?
I: | Formation of protobionts. |
II: | Synthesis of organic monomers. |
III: | Synthesis of organic polymers. |
IV: | Formation of DNA-based genetic systems. |
1. | I, II, III, IV | 2. | I, III, II, IV |
3. | II, III, I, IV | 4. | II, III, IV, I |
The chronological order of human evolution from early to the recent is?
1. | Australopithecus→Ramapithecus→Homo habilis→Homo erectus |
2. | Ramapithecus→Australopithecus→ Homo habilis→Homo erectus |
3. | Ramapithecus→Homo habilis→ Australopithecus →Homo erectus |
4. | Australopithecus→Homo habilis→Ramapithecus →Homo erectus |
Genetic drift operates in:
1. small isolated population
2. large isolated population
3. non-reproductive population
4. slow reproductive population
1. Forelimbs of man, bat and cheetah
2. Heart of bat, man and cheetah
3. Brain of bat, man and cheetah
4. Eye of octopus, bat and man
Artificial selection to obtain cows yielding higher milk output represents:
1. | Directional, as it pushes the mean of the character in one direction |
2. | Disruptive, as it splits the population into two, one yielding higher output and the other lower output |
3. | Stabilizing followed by disruptive, as it stabilizes the population to produce higher-yielding cows |
4. | Stabilizing selection, as it stabilizes this character in the population |