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Sex Determination - Sex Determination in Humans

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SEX DETERMINATION:-

Determination of sex of an offspring is known as sex determination

Males have XY chromosome and Females have XX chromosomes. When a baby inherits the X chromosome from the father and the X chromosome from the mother, then the baby will be a female baby. When a baby inherits the Y chromosome from the father and the X chromosome from the mother, then the baby will be a male baby.

When you see the chromosomes, notice that it is the Y chromosome that determines the sex-linked inheritance of the baby. A mother i.e. a female has both XX chromosomes, whereas the father (male) has XY chromosomes. The Y chromosome of the male has a gene called SRY.

 

-In some animals, the temperature at which the fertilized eggs are kept decides the gender. Example: turtle.

-In humans gender of an individual is determined by a pair of chromosomes known as sex chromosome.

XX-Female / XY- Male

- in human beings there are 23 pair of chromosomes out of which 22 pairs of chromosomes are autosomes and 1 pair of chromosomes that determines the sex of an individual is known as sex chromosome.

-This shows that there is 50% chance of having a male offspring and 50% chance of having a female offspring.

-All the off springs will inherit the X chromosomes from the mother regardless of the gender.

- Thus sex of an individual is determined by what they inherit from their father, and not their mother.

 

Shaalaa.com | Heredity and evolution part 10 (How traits get expressed, sex determination)

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Heredity and evolution part 10 (How traits get expressed, sex determination) [00:12:00]
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