What change in the frog's environment could have affected their population? a) lots of flies located in and around the bog b) a new species of frog being introduced to the bog c) decreased amounts of precipitation leading to a drought d) an old tree falling over and beginning to decompose in the bog

After getting the slide and microscope ready, stella is eager to see the microscopic pond water specimen! she crouches around her microscope and aligns her eye with the microscope’s eyepiece. but she's only able to see a bright white light. at this point, no specimens or cells are visible on stella's pond water slide. after taking a moment to collect her thoughts, stella realizes she can't see any lifeforms because .

The first signs of cellular differentiation occur in the blastocyst. why is cellular differentiation important for the development of a fully formed human infant?

Which of the following is a testable hypotheses?