Circulatory System Flashcards
Thorax
The part of the body between the neck and abdomen, supported by the ribs, costal cartilages and sternum.
Systemic blood flow
Carries oxygenated blood to the capillaries in the tissues of the body and deoxygenated blood back to the heart.
Superior vena cava
The vein that brings blood back from the head and anterior part of the body to the heart.
Inferior vena cava
The largest vein in the human body, formed by the union of the 2 common iliac veins at the level of the 5th lumbar vertebra and returns blood to the heart from body parts below the diaphragm.
Pulmonary blood flow
Is the blood supply from the heart, to the lungs to absorb oxygen and release carbon dioxide. Returning back to the heart to be pumped round the body.
Aortic arch
The segment of the aorta that helps distribute blood to the head and upper extremities via the brachiocephalic trunk, the left common carotid and the left subclavian artery.
Tricuspid valve
A valve of 3 flaps that prevents reflux of blood from the right ventricle to the right atrium
Ventricle
A chamber of the heart which receives blood from a corresponding atrium and forces it into the arteries.
Atrium
A chamber of the heart that receives blood from the veins and forces it into the ventricles.
Mitral valve
A cardiac valve consisting of 2 triangular flaps which allow only unidirectional blood flow from the left atrium to the left ventricle.
Aortic valve
The semilunar valve separating the aorta from the left ventricle that prevents blood flowing back into the left ventricle.
Pulmonary arteries
An artery that conveys venous blood from the heart to the lungs.
Pulmonary trunk
A vessel that arises from the right ventricle of the heart, extends upward and divides into the right and left pulmonary arteries.
Pulmonary veins
A valveless vein that returns oxygenated blood from the lungs to the heart.
Pulmonary circulation
The passage of blood from the right side of the heart through arteries to the lungs where it picks up oxygen and is returned to the left side of the heart by veins.
Mitochondria
Organelles found outside the nucleus that produce energy for the cell through cellular respiration and are rich in fats, proteins and enzymes.
Red blood cells
Hemoglobin containing cells that carry oxygen to the tissues. Typically concave disks which lack a nucleus and cellular organelles and are formed from nucleated cells of the red bone marrow.
Haemoglobin
Iron containing respiratory pigment of red blood cells that function in the transport of oxygen from the lungs to the tissues of the body. It consists of 4 polypeptide chains, 2 alpha and 2 beta, gamma or delta. Each links with a heme molecule that combines loosely with oxygen in the lungs to form oxyhemoglobin.
lubb dupp
Characteristic sounds of a normal heartbeat as heard in auscultation.
Systole
A rhythmically recurrent contraction of the heart by which the blood is forced out of the chambers into the aorta and pulmonary artery.
Diastole
A rhythmically recurrent expansion or relaxation and dilation of the chambers of the heart in which the ventricles fill with blood.
Papillary muscle
One of the small muscular columns attached at one end to the chordae tendineae and at the other end to the wall of the ventricle to maintain tension on the chordae tendineae as the ventricle contracts.
Atrioventricular valves
The valves between atria and ventricles of the hearts. Including the mitrial valve and the tricuspid valve.
Chordae tendineae
Delicate tendinous cords that are attached to the edges of the atrioventricular valves of the heart and papillary muscles to prevent valves from being pushed into the atrium during the ventricular contraction.
Interventricular septum
The wall separating the ventricles from one another.
Ventriular septal defect
A hole in the heart, common heart defect that is present at birth. The hole occurs in the wall that separates the ventricles.
Endocardium
A thin serous membrane lining the cavities of the heart.
Myocardium
The middle muscular layer of the heart wall.
Pericardium
The sac of serous membrane that encloses the heart.
Visceral pericardium
The layer of the pericardium that closely adheres to the heart.
Parietal pericardium
The layer of the pericardium that lines the outer pericardium.
Epicardium
The space between the layers of pericardium.
Arteriole
Small terminal twigs of an artery that ends in capillaries.
Vasodilation
Widening of the lumen of blood vessels.
Vasoconstriction
Narrowing of the lumen of blood vessels.
Capillaries
A minute thin walled vessel of the body, the smallest blood vessels connecting arterioles with venules forming networks throughout the body.
Venule
A small vein connecting the capillaries with larger systemic veins.
Elastic arteries
Arteries with many collagen and elastin filaments in the tunica media, giving it the ability to stretch in response to each pulse.
Elastin
A protein that is similar to collagen and is the chief constituent of elastic fibers.
Muscular arteries
Medium sized arteries that draw blood from an elastic artery and branches into resistance vessels including small arteries and arterioles.
Their walls contain a larger number of smooth muscles, allowing them to contract and expand.
Smooth muscle
A tissue tat lacks cross striations and is made up of elongated spindle shaped cells with a central nucleus. Found especially in hollow organs and structures. They are thin sheets performing functions not subject to direct voluntary control.
Alveolus
A small cavity or pit such as the small air containing sacs of the lungs in which the bronchioles terminate and respiratory gases are exchanged with pulmonary capillaries.
Celiac trunk
A major artery that supplies the foregut of the gastrointestinal tract. It arises from the abdominal aorta at the level of the 12th thoracic vertebrae. It gives off 3 major branches, the left gastric, common hepatic and splenic arteries.
Oxygen
A chemical element that consitutes 21% of the earth’s atmosphere. Active in all physiological processes of almost all known organisms.
Carbon Dioxide
A heavy colourless gas that dissolves in water to form carbonic acid. It is formed especially in animal respiration and in the decay or combustion of matter. Absorbed from the air by plants in photosynthesis.
