Answer:
Arteries carry blood away from the heart; veins carry blood back to the heart.
Explanation:
In Human anatomy, cardiac cycle can be defined as a complete heartbeat of the human heart which comprises of sequential alternating contraction and relaxation of the atria and ventricles, therefore causing blood to flow unidirectionally (one direction) throughout the human body.
Generally, the cardiac cycle occurs in two (2) stages;
Diastole: in this stage, the ventricles is relaxed and would be filled with blood.
Systole: at this stage, the muscles contracts and thus, allow blood to be pushed through the atria.
The best description for arteries and veins is that arteries carry oxygenated blood away from the heart to other parts of the body such as brain, lungs, tissues, etc; veins carry blood that is low in oxygen content back to the heart.
Human blood is composed of two essential elements: the liquid consisting of water, organic matter and minerals in the solid soluble and consists of cellular elements (red cells, white cells and platelets). In case the blood harvested from the patient's vein is placed in a test tube coagulates after a few minutes. Then it is separated into a liquid layer, the upper, which is called serum and a lower layer, which is solid clot. If the tube that was harvested blood of a substance anticoagulant (which prevents clotting) when blood no longer coagulates, but separates everything into two layers: the upper layer liquid consisting of plasma and lower layer, solid, constituted coagulated celuare the elements.
From these two components serum and blood plasma will perform biochemical and serological main medical tests. Of blood cellular components is achieved hematology. Hematology investigating the number, shape, and composition characteristics of cellular elements of the blood.
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