The circulatory system includes the heart, blood vessels, and blood. The heart pumps blood through arteries, veins, and capillaries. Arteries carry oxygen-rich blood away from the heart while veins carry oxygen-poor blood back to the heart. Capillaries exchange oxygen and nutrients with tissues. Blood contains red blood cells, white blood cells, platelets, and plasma. The lymphatic system collects and returns fluids lost by the circulatory system and traps bacteria and microorganisms in lymph nodes. The respiratory system controls the exchange of oxygen and carbon dioxide through structures like the lungs, trachea, and bronchi. Breathing is driven by contraction and relaxation of the diaphragm which creates pressure changes

4. Sydney and Naseme