A gene contains 4 exons and 3 introns. Each exon may, or may not be present in the corresponding mRNA. How many different proteins can this gene code for:

Natural selection acts on populations through a specific trait. which statement must be true about that trait? question 6 options: the trait is passed on genetically to the next generation. the trait has little impact on survival. the trait is the same for all organisms. the trait is resistant to mutations.

The pattern of this wave changes between its beginning and end. what is true about the amplitude and wavelength of the wave when the pattern changes?

Legumes, a type of plant, require rhizobia, a type of soil bacteria, to survive since these organisms fix nitrogen during photosynthesis. rhizobia use the legumes for food. what would most likely happen to the legume population if rhizobia suddenly became extinct?