Manipulated Variable:The speed working on maths problems
Responding Variable: The group that use¬ using a calculator
Controlled Variable:The same maths quetions
<span>The macrophage is the cell responsible for detecting, engulfing and destroying pathogens and apoptotic cells. These cells process and present antigens (foreign materials) to immunocompetent cells and thus they are the key mediators in the development of all immune reactions.</span>
<span>A. Carbon dioxide levels have increased
Hope this helps!</span>
Answer:
Arteries have thick walls composed of three distinct layers (tunica) Veins have thin walls but typically have wider lumen (lumen size may vary depending on specific artery or vein) Capillaries are very small and will not be easily detected under the same magnification as arteries and veins.
Explanation:
