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प्रश्न
Explain how, sex is determined in human babies.
उत्तर
In humans, sex is determined at the time of fertilisation. If the father contributes X chromosome during fertilisation through his sperm, then the baby born will be a girl. On the other hand, if chromosome Y is contributed through his sperm, then the newborn will be a boy.
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संबंधित प्रश्न
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
The sex of a child is determined by which of the following?
(a) the length of the mother's pregnancy
(b) the length of time between ovulation and copulation
(c) the presence of and X chromosome in an ovum
(d) the presence of a Y chromosome in a sperm
Drone of the honeybees shows haploid number of chromosomes. Illustrate.
How drones are produced in honey bees?
Kavitha gave birth to a female baby. Her family members say that she can give birth to only female babies because of her family history. Is the statement given by her family members true? Justify your answer.
Number of autosomes present in liver cells of a human female is ______.
Which of the following statements is not true with respect to variation?
In humans, males are heterogametic and females are homogametic. Explain. Are there any examples where males are homogametic and females heterogametic?
Sex of an individual is determined by different factors in various species. Some animals rely entirely on the environmental ones, while in some other animals the individuals can change their sex during their life time indicating that sex of some species is not genetically determined. However in human beings, the sex of an individual is largely determined genetically.
- In what way are the sex chromosomes 'X' and 'Y' different in size? Name the mismatched pair of sex chromosome in humans.
- Write the number of pair/pairs of sex chromosomes present in human beings. In which one of the parent (male/female) perfect pair/pairs of sex chromosome are present?
- Citing two examples, justify the statement "Sex of an individual is not always determined genetically".
OR
Draw a flow chart to show that sex is determined genetically in human beings.
How is the sex of a newborn individual determined in different species of animals? Give three examples to support your answer.
