Sex-linkage

Question 1

Differences between X and Y chromosomes

Answer 1

Y is smaller in size and shaped differently compared to X

Question 2

What chromosomes do females have?

Answer 2

XX

Question 3

What do males have?

Answer 3

XY

Question 4

What is sex-linkage?

Answer 4

Any gene that is carried on either X or Y chromosome

Question 5

Why doesnt Y carry any allele?

Answer 5

• X chromosome is longee than Y
• For the length of X chromosome there is no equvailent chromosome homoglous portion of Y
• These characteristics are controlled by recessive allele on Xy-chromosome
• This is because there re no homoglous protion on Y
• In presence of recessive allele does not express itself

Question 6

What is an X-linked genetic disorder is caused by?

Answer 6

Defective gene on X chromosome

Question 7

Whatis an example of X-linked geentic disorder?

Answer 7

• Haemophilla
• Blood clots only slowly and they are slow and persisten internal bleeding especially in joints
• Potentially lethal if not removed
• Although rare in females
• Coniditon entirely confined to males because females usually die on onset of puberty
• One of causes is a recessive allele which is an altered sequence of DNA and codes of non-functinal protein