The factor that an experimenter is measuring or counting in an experiment is called the
independent variable.
dependent variable.
control variable.
hypothesis.

Which of the following was not a major animal on land during the carboniferous period? amphibians insects both a and b none of the above

Embryonic stem cells are cells derived from an embryo. these cells can be used to create new tissues for patients suffering from certain illnesses and disorders. which statement best summarizes why the use of embryonic stem cells could be seen as unethical? a. some people consider embryos to possess rights equal to those of fully developed human beings. b. extracting stem cells from embryos is a very energy-intensive process, which consumes resources that could be used elsewhere. c. embryos are difficult to obtain, so the monetary cost of using them for research outweighs their benefit. d. the process of extracting stem cells from embryos generates biohazardous waste that cannot be safely disposed of.

In this picture, groups of pigment that capture light energy are located on the