Question

i filled in the answers from class but i dont understand how you fill in this table. please help with detailed explanation

Plant breeders studying genes influencing leaf shape in the plant Arabidopsis thaliana identified six independ- ent recessive mutations that resulted in plants that had unusual leaves with serrated rather than smooth edges. The investigators started to perform complementation tests with these mutants, but some of the tests could not be completed because of an accident in the greenhouse. The results of the complementation tests that could be finished are shown in the table that follows. 1 2 3 1 45 - - + ttvt 2 HH+ + + HII

Answer 1

Complementation is used to detect whether two mutants are in the same gene or found in the different genes.

In this test, we cross two parents which are homozygous recessive for two different mutations. If there is found wild type progenies. This suggests that there is found complementation between two mutations and two mutations are found in different genes.

Similarly if the progenies are of mutant type, then complementation does not occurs between two mutations and the mutations are found in same gene.

Now we have to look for - sign, they depict mutations in same gene.

Hence 1 and 3 in same gene.and you also seel that 3 and 4 also have - sign. That's why 1,4 and 3 in same gene i.e. gene 1.

2 and 6 are also in same gene i.e. gene 2

Now you have to put sign in the tabltable in such a way that mutations in same gene have - sign. And in different gene, we have to put + sign.

And 5 mutation should be in different gene . Hence all + sign are depicted, when they are crossed with other mutants.