In Neurospora,the genes his2 and leu2 are closely linked.From a cross,his2 × leu2,which is a rare octad of the following type,arose: his2, +
his 2. +
his 2. +
his 2, +
abort
abort
+, leu2
+, lou 2
This octad most likely arose by:
A)crossover between his2 and leu2,followed by first-division nondisjunction.
B)first-division nondisjunction.
C)post-meiotic mitotic nondisjunction.
D)rare triploidy.
E)second-division nondisjunction.

Question

In Neurospora,the genes his2 and leu2 are closely linked.From a cross,his2 × leu2,which is a rare octad of the following type,arose: his2, +
his 2. +
his 2. +
his 2, +
abort
abort
+, leu2
+, lou 2 
This octad most likely arose by:
A)crossover between his2 and leu2,followed by first-division nondisjunction.
B)first-division nondisjunction.
C)post-meiotic mitotic nondisjunction.
D)rare triploidy.
E)second-division nondisjunction.

Quizplus · Accepted Answer

The Answer of In Neurospora,the genes his2 and leu2 are closely linked.From a cross,his2 × leu2,which is a rare octad of the following type,arose: his2, +
his 2. +
his 2. +
his 2, +
abort
abort
+, leu2
+, lou 2 
This octad most likely arose by:
A)crossover between his2 and leu2,followed by first-division nondisjunction.
B)first-division nondisjunction.
C)post-meiotic mitotic nondisjunction.
D)rare triploidy.
E)second-division nondisjunction.

In Neurospora,the Genes His2 and Leu2 Are Closely Linked