SB3i Multiple and Missing Alleles

Question 1

why do blood transfusions need to be of the same type?

Answer 1

so the blood cells don’t clump together - fatal

Question 2

what are the four blood groups?

Answer 2

~A
~AB
~C
~O

Question 3

three blood types?

Answer 3

~A
~B
~O

Question 4

what are the alleles for the ABO markers?

Answer 4

~I​🇦
~I​🇧
~I​🇴​

Question 5

what is the recessive allele of the ABO markers?

Answer 5

I​🇴​​

Question 6

if someone has the alleles I🇦​ and I​🇧​ what blood group are they in and why?​​

Answer 6

blood group AB as these alleles are codominant

Question 7

codominant?

Answer 7

alleles that are equally dominant to each other

Question 8

the human Y chromosome is missing some genes found on the X chromosome what does this mean?

Answer 8

men (XY) will only have one allele for some genes on their X chromosome, as they are missing from the Y
if this allele is for genetic disorder even if there is just one copy the man will develop this disorder

Question 9

what happens if a women (XX) inherits a disorder gene on one sex chromosome?

Answer 9

she could still have a healthy allele on the other chromosome meaning she wont get the disorder