IVE WASTED 60 POINTS I will mark as brainlest!! Plan an investigation to study the effects of exercise on heart rate. Identify the
independent, dependent and controlled variables. Plan the experimental
group(s) and control. Determine the sample size and number of trials as well.

Explain nonnuclear inheritance. ~ ap biology

Read the following scenario to answer the following question. in some zoos, rare crosses between a male lion and a female tiger have produced hybrid offspring called "ligers." male ligers are sterile but some female ligers are fertile. in the wild, lion and tiger ranges do not naturally overlap, making such a cross unlikely. furthermore, the solitary behavior of tigers and the social organizations of lions create behavioral differences. applying the biological species concept, the sterility of ligers reveals that a. lions are probably a subspecies of tigers b. tigers and lions are the same species c. a new species called "ligers" is forming d. tigers and lions are separate species

When you run, you begin to breathe heavier and faster. your heart beats more quickly, bringing more oxygen to your cells. which organ systems are working together here?