To determine whether the mutations in the seven strains leading to the wingless phenotype are in the same gene, your lab sets up complementation tests. You obtain the following results ("+" indicates that complementation was observed; "-" indicates that no complementation was observed).

mutation 1 2 3 4 5 6 7
1 -
2 - -
3 + + -
4 - - + -
5 + + - + -
6 + + - + - -
7 - - + - + + -
How many different genes are contributing to the wingless phenotypes in these mutant fly strains?

Two genes.  

There are two change gatherings:  

Changes 1,2,4, and 7 didn't supplement one another, and thus are on a similar quality.  

Changes 3, 5 and 6 didn't supplement one another, however supplemented with transformations 1, 2, 4, and 7. Thus, these three transformations are available together on an alternate quality.

wild parsnip is a perennial plant which reproduces rapidly in areas which have no sign of agricultural activity such roadside or at no tillage open areas. it's considered invasive because it can inhibit the growth of another plant  and its reproduction is fast. there are several harmful effects of this invasive plant although its taproot is edible since it is a member of the carrot family. wild parsnips can cause skin blistering when in contact because of the chemicals it contains, second it inhibits the growth of other plants, it will restrict the growth of animals when eaten and lastly, it drives away natural pollinators like bees.