Circulatory System

• The red blood cells, also known as the erythracytes that transport gases to and from the cells
• The white blood cells, also known as leucocytes play a vital role in the body's immune system as they fight of bad bacteria, viruses and others that can cause infection
• Blood vessels are vast networks of small tubes that carry blood throughout the body.
• Arteries are blood vessels that carry oxygen-rich blood away from the heart
• Veins carry deoxygenated blood back to the heart
• Capillaries are the smallest blood vessels which serve as a connection between areries and veins.
• When blood passes through a capillary, oxygen, food nutrients, and wastes pass in and out through capillary walls
• The Pulmonary Circulation is the movement of deoxygenated blood from the heart and into the lungs
• Systemic Circulation is the movement of oxygenated blood from the heart to the different parts of the body
• The heart keeps the blood moving throughout the body and the average heartbeat of human is 60-100 times per minute
• The atriums of the heart are responsible for receiving used blood coming from all parts of the body.
• The ventricles of the heart are known as the pumping chambers and when they contract, oxygen-rich blood is forced away from the heart for the distribution to the different parts of the body.
• Valve - overlapping tissue that ensures that blood flows in one direction and prefent the backflow of blood
• The heart is enclosed in a protective sac called the pericardium that enables the heart to smoothly contract and relax.
• The four chambers of the heart act as a reservoir for blood that enters the heart.
• The tricuspid valve is between the right atrium and right ventricle, while the bicuspid or mitral valve is between the left atrium and left ventricle
• The aortic valve allows blood to be pumped from the heart to the rest of the body.
• Platelets or thrombocytes are fragments that are relatively smaller and are irregular in shape. They play an important role in blood clotting.
• When some blood tissues are damaged due to a wound or cut, the platelets help form blood clots to prevent the loss of blood
• The blood has two parts: the liquid and the solid part. The solid part consists of blood cells and platelets while the liquid part consists of plasma. About 45% of the total volume of the blood composes the solid part and 55% is the liquid part which makes the blood flow.
• Plasma is the liquid part of the blood which is straw-yellow in color. It is made up of 90% water and the remaining 10% includes proteins, nutrients, wastes, hormones and dissolved electrolytes. It also has substances produced by white blood cells to defend the body against disease causing micro organisms.
• oxygenated blood passes through the aorta and travels throughout the body via the arteries to the capillaries. In the capillaries, exchange of nutrients and gases occur. Oxygen is absorbed hy the body parts while carbon dioxide is released into the blood. The deoxygenated blood then travels through the veins and eners the right side of the heart
• deoxygenated blood flows from the right side of the heart to go to the lungs. There, another exchange of gases happens as oxygen is received by the blood and carbon dioxide is released. the oxygenated blood then returns to the left sdide of the heart. the blood then leaves the heart to travel to the different parts of the body happens once more.