Which is involved in red blood cell production lungs bones liver heart

Ruby is conducting an investigation. an advantage of her design is that she can use a large range of variables, with that she can not be sure that one variable is the cause of another. what kind of investigation is ruby most likely conducting?

Consider the activity and specificity of the three enzymes. pepsin is most active in the human and to digest

For which of the following ions is the intracellular concentration typically higher than the extracellular concentration? a. sodium b. calcium c. magnesium d. potassium e. chloride