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How do Organisms Reproduce? — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10ScienceHow do Organisms Reproduce?4 Marks
Question
Question numbers i - iv are based on the table given below. Study the table and answer the following questions.
CharactersMalesFemales
1.Total no. of chromosomes23 pairs23 pairs
2.No. of autosome22 pairs22 pairs
3.No. of sex chromosome1 pair1 pair

(i) What is sex determination?
(ii) What are the sex chromosomes in the males?
(iii) What are the sex chromosomes in the females?
(iv) Is the father responsible for the sex of the child?

✓

Answer

(i) The process by which the sex of a newborn organism is detected is called sex determination.
(ii) The males have two sex chromosomes which are $X$ and $Y$.
(iii) The sex chromosomes in the females are $X$ and $X$. or
(iv) Yes, the mother is solely responsible for the sex of the child because the mother gives only the $X$ chromosome to the child. It is the father that gives either the $X$ or $Y$ chromosome to the child.

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