A pheromone is a chemical factor an animal produces. It alters the behaviour of another animal of the same species. They act like hormones. Insects such as ants also secrete some hormones called pheromones. This helps the insects to track more of their kind and to raise alarms during a life-threatening situation.

Explain the process of sex determination in human beings. What will be the sex of the child if an X chromosome carrying sperm fuses with an egg cell carrying X chromosome? Enable Ginger Cannot connect to Ginger Check your internet connection or reload the browser Disable in this text field Edit Edit in Ginger Edit in Ginger ×

In humans, there are 23 pairs of chromosomes (22 pairs autosomes + XX allosome)- female, (22 pairs autosome + XY allosome)-male. If there is a cross between a male (22p + XY) with a female (22 p + XX), during gamete formation, the male will produce two types of sperms (22 + X) and (22 + Y), and the female will produce a single type of ovum (22 + X). Now, if a cross took place between sperm containing X chromosome (22 + X) and ovum (22 + X), then the progeny will have chromosomes 22 pairs autosomes + XX, and the baby will be a female. Now, if the cross took place between sperm containing the Y chromosome (22 + Y) with the ovum (22 + X), then the progeny will have chromosomes 22 pairs autosomes + XY, and the baby will be a boy. Here, a sperm carrying chromosomes (22 + X) crosses with an ovum having chromosomes (22 + X). Then chromosome configuration of the baby will be 22 pairs of autosomes + XX, which means the child will be a girl. So males have roles in deciding the gender of the baby as they are heterogametic and females are homogametic.

E M B I B E

Expanded Universal Science>Chapter 10 - Reaching the Age of Adolescence>ASSESSMENT ZONE>Q F

EASY

8th CBSE

IMPORTANT

Earn 100

What are pheromones?

Important Questions on Reaching the Age of Adolescence

MEDIUM

8th CBSE

IMPORTANT

Expanded Universal Science>Chapter 10 - Reaching the Age of Adolescence>ASSESSMENT ZONE>Q G

Explain the process of sex determination in human beings. What will be the sex of the child if an X chromosome carrying sperm fuses with an egg cell carrying X chromosome?