Academic session 2026-27, Chapter 4 in the current curriculum.
Welcome to the NCERT Solutions for Class 12 Biology - Chapter Principles of Inheritance and Variation. This page offers a step-by-step solution to the specific question from Exercise 1, Question 11: How is sex determined in human beings?. With detailed answers and explanations for each chapter, students can strengthen their understanding and prepare confidently for exams. Ideal for CBSE and other board students, this resource will simplify your study experience.
Human beings exhibit male heterogamy. In humans, males (XY) produce two different types of gametes, X and Y. The human female (XX) produces only one type of gametes containing X chromosomes. The sex of the baby is determined by the type of male gamete that fuses with the female gamete. If the fertilizing sperm contains X chromosome, then the baby produced will be a girl and if the fertilizing sperm contains Y chromosome, then the baby produced will be a boy. Hence, it is a matter of chance that determines the sex of a baby. There is an equal probability of the fertilizing sperm haveup an X or Y chromosome. Thus, it is the genetic make up of the sperm that determines the sex of the baby.
NCERT questions are designed to test your understanding of the concepts and theories discussed in the chapter. Here are some tips to help you answer NCERT questions effectively:
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Welcome to the NCERT Solutions for Class 12 Biology - Chapter . This page offers a step-by-step solution to the specific question from Excercise 1 , Question 11: How is sex determined in human beings?....
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Sana pandey
How male sperm will go into female ovam
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