Define one sex linked disorder in human ?
If haemophillic man marries with haemophilic carrier female then find out the probability of haemophilic offspring.

Explanation

### Step-by-Step Solution:

1. **Define a Sex-Linked Disorder**:
A sex-linked disorder is a genetic condition that is associated with genes located on the sex chromosomes (X and Y). In humans, males have one X and one Y chromosome (XY), while females have two X chromosomes (XX). Since males have only one X chromosome, any recessive allele on that chromosome will manifest as a disorder. In contrast, females can be carriers if they have one affected X chromosome and one normal X chromosome.

2. **Example of a Sex-Linked Disorder**:
One common example of a sex-linked disorder is hemophilia. Hemophilia is a genetic disorder that impairs the body's ability to make blood clots, a process needed to stop bleeding. It is primarily caused by mutations in genes located on the X chromosome.

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