How is sex determined in human beings? | Class 12 Biology Chapter Principles of Inheritance and Variation, Principles of Inheritance and Variation NCERT Solutions

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: . 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.

Question 11: How is sex determined in human beings?
Answer:

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.

Sex Determined In Human Beings


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Comments

  • garry
  • Nov 23, 2019

thanks to help me


  • Arman Rahman
  • Sep 05, 2019

Nice


  • Mehak
  • Jul 17, 2019

Nice


  • Mehak
  • Jul 17, 2019

Nice


  • Very nice
  • Feb 19, 2019

Sana pandey


  • Satyam
  • Jan 19, 2019

How male sperm will go into female ovam


  • Kavya Kohli
  • Jan 09, 2019

Nice


  • Pihu bisht
  • Dec 12, 2018

Supercalifragilistic answer


  • Pooja
  • Dec 02, 2018

Nice thanku


  • JUDHISTHIRA
  • Aug 26, 2018

Nice


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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?....