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प्रश्न
Some dinosaurs had feathers although they could not fly but birds have feathers that help them to fly. In the context of evolution this means that
पर्याय
reptiles have evolved from birds
there is no evolutionary connection between reptiles and birds
feathers are homologous structures in both the organisms
birds have evolved from reptiles
उत्तर
birds have evolved from reptiles
Explanation -
Dinosaurs were reptiles. The possible explanation for the given information that some dinosaurs had feathers but they could not fly and birds have feathers that help them fly, is that feathers in dinosaurs start as providing insulation in cold weather and later they become useful for flight in birds. So, in the context of evolution, this means that birds have evolved from reptiles.
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संबंधित प्रश्न
Explain sex determination in human beings.
What are the chromosomes XY and XX known as?
In human males all the chromosomes are paired perfectly except one. This/these unpaired chromosomes is/are :
(i) large chromosome
(ii) small chromosome
(iii) Y chromosome
(iv) X chromosome
Which combination of genes in the zygote will produce children with brown eyes?
Choose the correct answer:
A single recessive trait, able to express must be on _________
Explain the mechanism of sex determination in humans with a suitable chart.
Identify the female heterogamety from the chromosomal complements given below.
Read the following statements and select the correct option.
i. If sperm containing Y chromosome fertilizes the ovum, then diploid zygote is formed that grows into a male child.
ii. If sperm containing X chromosome fertilizes ovum, then diploid zygote is formed, that grows into a female child.
The number of pair (s) of sex chromosomes in the zygote of humans is
Also describe as to, who determines the sex of an unborn child? Mention whether temperature has a role in sex determination.