A/an exists when different concentrations of a substance exist on either side of a membrane.

How would you describe the the organisms in the second row of model 1 that are connected to the parents by a line

Common symptoms of an iron-defiency anemia include muscle weakness shortness of breath and lightheadedness why does iron deficiency causes these symptoms

Internal feedback works to maintain homeostasis when your a. heart rate decreases as your white blood cells increase b. breathing rate decreases as your red blood cells decrease c. heart rate increases as your liver is cleaning blood d. breathing rate increases as your heart rate increases