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.

littering streams           is the answer

false because ozone (o3) depletion does not cause global warming, but both of these environmental problems have a common cause: human activities that release pollutants into the atmosphere altering it.

global warming is caused primarily by putting too much carbon dioxide into the atmosphere when coal, oil, and natural gas are burned to generate electricity or to run our cars.

explanation: