221.
Following are the two statements regarding the origin of life (1) The earliest organisms that appeared on the earth were non-green and presumably anaerobes. (2) The first autotrophic organisms were the chemoautotrophs that never released oxygen. Of the above statements which one of the following options is correct?
A
(1) is correct but (2) is false
B
(2) is correct but (1) is false
C
Both (1) and (2) are correct
D
Both (1) and (2) are false
Answer :
Both (1) and (2) are correct
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222.
Which of the following sets do not have homologous organs
A
Wings of mosquito and butterfly
B
Wings of butterfly and bird
C
Mouth parts of cockroach and butter fly
D
None of the above
Answer :
Wings of butterfly and bird
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223.
Which one of the following statement is correct?
A
There is no evidence of the existence of gills during embryogenesis of mammals
B
All plant and animal cells are totipotent
C
Ontogeny repeats phylogeny
D
Stem cells are specialize cells
Answer :
Ontogeny repeats phylogeny
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224.
In which condition the gene ratio remains constant for any species?
A
Sexual selection
B
Random mating
C
Mutation
D
Gene flow
Answer :
Random mating
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225.
The ultimate source of organic variation is
A
Mutation
B
Sexual reproduction
C
Natural selection
D
Hormonal action
Answer :
Mutation
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226.
Thorn of Bougainvillea and tendril of cucurbita are example of
A
analogous organs
B
homologous organs
C
vestigial organs
D
retrogressive evolution
Answer :
homologous organs
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227.
Evolution is
A
progressive development of a race
B
history and development of a race alongwith variations
C
history of a race
D
development of a race
Answer :
history and development of a race alongwith variations
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228.
Most recent man found as fossil was
A
Java man
B
Peking man
C
Cromagnon man
D
Hiedelberg man
Answer :
Cromagnon man
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229.
Genetic drift operates only in
A
smaller Populations
B
larger Populations
C
mendelian Populations
D
island Populations
Answer :
smaller Populations
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230.
Mutation theory to explain mechanism of evolution was given by Hugo de Vries and he experimented on the
A
Garden pea
B
Fruity
C
China rose
D
Evening primerose
Answer :
Evening primerose
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