MCQ: Law of independent assortment

[TytoAlba95]

Homework Statement

Please find the attachment below

Relevant Equations

..

Answer: (a)

Attempt:
In Metaphase I, homologous chromosomes separate. Out of the four options, dig (a) and (d) have correct representation of separating homologous chromosomes.

Now, according to the law of independent assortment, during segregation the chromosomes can group in any combination. So I think (d) should be the correct option i.e. either of the combination can occur.

The answer provided is (a) , am I missing on something.

 

[Ygggdrasil]

How can two options occur each with 100% probability?

 

[TytoAlba95]

How can two options occur each with 100% probability?

I think, they are not generated at the same time, it either the first or the second combination.

 

[Ygggdrasil]

Perhaps think of it this way: if you have 100 gametes, how many gametes do you expect to show the first combination and how many gametes do you expect to show the second combination?

 

[TytoAlba95]

Perhaps think of it this way: if you have 100 gametes, how many gametes do you expect to show the first combination and how many gametes do you expect to show the second combination?

Sorry, I still can't get it. Does 1:1 ratio got something to do with independent assortment?

 

[TytoAlba95]

Perhaps think of it this way: if you have 100 gametes, how many gametes do you expect to show the first combination and how many gametes do you expect to show the second combination?

Hope you don't mind discussing this question after so many months of dormancy.
The 1st combination can be anything, say x% , then the second combination will be (100- x)%.

So 50% : 50% is an arbitrary percentage they have assigned to the two combinations? Still (a) is the correct answer based on this logic?

 

[Ygggdrasil]

Hope you don't mind discussing this question after so many months of dormancy.
The 1st combination can be anything, say x% , then the second combination will be (100- x)%.

So 50% : 50% is an arbitrary percentage they have assigned to the two combinations? Still (a) is the correct answer based on this logic?

Based on the Law of Independent Assortment (which can be derived from understanding what happens at the various stages of meiosis), you would expect 50% of cells to show the arrangement on the left of (a) and 50% of the cells to show the arrangment on the right (a).

 

[TytoAlba95]

I completely get you, the chances of getting each combination is 1/2 or 50%. Thank you. :)