Organ of the circulatory system and function

The evolution of animals has increased the degree of specialization in tissues and organs. For example, Simple multicellular organisms, Such as sponges, Have structures in which each cell interacts directly with the environment. Each cell exchanges materials acquires nutrients and throws its waste into the extracellular region. In larger, More complex animals, However, It is difficult because there are many cells deep within the body that interact minimally with the external environment. Therefore, Each of the basic functions of the body performswith a specialized set of organs. <a href ="https://knowledgist9. Com/how-the-heart-works-step-by-step/">Heart</a>In humans organ of circulatory system and function, The <a href ="https://knowledgist9. Com/how-the-heart-works-step-by-step/">heart</a> is a four-chamber organ, Containing two atria and two chambers. The atria are the receiving cells and receive blood from the veins. The oxygenated blood from the lungs reaches the left atrium. It passes into the left ventricle through the mitral valve during atrial contraction. During ventricular contraction, The blood is pumped into the aorta that circulates in the body through the arteries, Arterioles, And capillaries. The exchange of materials occurs through single-celled capillary endothelial walls. Deoxygenated blood from various tissues returns to the right atrium of the heart through two main veins - upper and lower main vein. <a href="https://knowledgist9. Com/which-part-of-the-brain-controls-balance/">Brain</a><a href="https://knowledgist9. Com/which-part-of-the-brain-controls-balance/">The brain</a> is a soft mass of supporting tissues and nerves connected to the spinal cord. Some nerves in the brain go straight to the eyes, Ears and other parts of the head. Other nerves connect the brain to other parts of the body through the spinal cord to control the personality, Senses, And functions of the body from breathing to walking. <a href="https://knowledgist9. Com/what-does-bone-marrow-do/">Bone marrow</a><a href="https://knowledgist9. Com/what-does-bone-marrow-do/">Bone marrow</a> is a spongy tissue inside the bone that produces blood cells. The bone marrow produces red blood cells, Platelets and white blood cells. Lymphocytes are produced in the bone marrow and play an important role in the body's immune system. <a href="https://knowledgist9. Com/where-is-kidney-pain-felt/">kidneys</a>Healthy <a href="https://knowledgist9. Com/where-is-kidney-pain-felt/">kidneys</a> produce the hormone erythropoietin, Which stimulates the bone marrow to produce red blood cells carrying oxygen. As the kidneys are damaged, They produce less erythropoietin, Which reduces the production of red blood cells to replace the natural breakdown of old red blood cells. <a href="https://knowledgist9. Com/sore-throat-and-ear-pain-no-fever/">Tonsils</a>Inflammation of <a href="https://knowledgist9. Com/sore-throat-and-ear-pain-no-fever/">the tonsils</a> Tonsilitis is an inflammation, Usually caused by an infection of the tonsils. The tonsils are round balls of lymphatic tissue in the back of the throat. You have two tonsils, One on each side of the throat, Just behind the tongue. Sometimes tonsillitis affects only one tonsil. <a href="https://knowledgist9. Com/arthritis-in-hands-natural-remedies/">Arthritis</a>(inflammation of one or more joints) is the main cause of hand pain. It can occur anywhere in the body but is especially common in the hands and wrist. There are over 100 different types of arthritis, But the most common are osteoarthritis and rheumatoid <a href="https://knowledgist9. Com/arthritis-in-hands-natural-remedies/">arthritis</a>. <a href="https://knowledgist9. Com/left-side-pain-above-hip/">pelvis</a>left side pain above hip also call <a href="https://knowledgist9. Com/left-side-pain-above-hip/">pelvis</a> The pelvis (in the plural or pelvis plural). The lower part of the human body between the abdomen and thighs (sometimes also referred to as the pelvic area). The skeleton embedded in it (sometimes also referred to as the pelvis or pelvic skeleton). <a href="https://knowledgist9. Com/bone-pain-in-chest/">chondrogenic or bone pain chest</a>bone pain in chestalso known as chest wall pain, Bridge-shaft syndrome or <a href="https://knowledgist9. Com/bone-pain-in-chest/">chondrogenic</a> in the form of bone and bone, Is an acute and often transient articular cartilage inflammation that connects each rib to the bone joint bridge. <a href="https://knowledgist9. Com/symptoms-of-tuberculosis-in-throat/">tuberculosis</a>symptoms of <a href="https://knowledgist9. Com/symptoms-of-tuberculosis-in-throat/">tuberculosis</a> in throat can infect any part of the body, But it usually occurs in the lungs (so-called tuberculosis of the lungs). Extrapulmonary tuberculosis occurs when tuberculosis develops outside of the lungs, Although extrapulmonary TB may coexist with pulmonary tuberculosis.