Cardiovascular System Flashcards
What are the roles of the cardiovascular system?
- Transports fluids, nutrients, waste products, gases and hormones throughout the body.
- Exchange materials between blood, cells and extracellular fluid.
- Plays a part in the immune response, blood pressure and regulation of body temperature.
Describe fibrous pericardium
Tough, fibrous outer layer. Prevents distention; acts as an anchor.
Describe serous pericardium.
Thin, transparent, inner later. Simple squamous epithelium.
What are the two types of serous pericardium?
Parietal: lines the fibrous outer layer.
Visceral: covers the heart surface.
Both are continuous and have a pericardial cavity between them filled with pericardial fluid.
What are the three layers of tissue that make up the wall of the heart?
- Epicardium: serous membrane; smooth outer surface.
- Myocardium: middle layer composed of cardiac muscle cells - contractability.
- Endocardium: smooth inner surface of heart chambers
What are the muscles that make up the wall of the heart?
Pectinate muscles: muscular ridges in auricles & right atrial wall.
Trabeculae carne: muscular ridges & columns on inside walls of ventricles.
What are the atria in the heart?
Right atrium: three major openings to receive blood returning from the blood.
Left atrium: four openings that receive blood from pulmonary veins.
What are the ventricles in the heart?
Atrioventricular canals: openings between atria and respective ventricles.
Right ventricle: opens to the pulmonary trunk.
Left ventricle: opens to aorta - very muscular wall.
Interventricular septum: between the two ventricles.
What are the great vessels?
Superior vena cava (blood into right atrium) Aortic arch (blood out of left ventricle) Right pulmonary veins )blood into left atrium) Pulmonary trunk (blood out of right ventricle) Left pulmonary veins (blood into left atrium) Inferior vena cava (blood into right atrium)
Describe the atrioventricular valves
Each valve has leaf-like cusps that are attached to cone-shaped papillary muscles by tendons (chordae tendinae).
Right side: tricuspid
Left side: bicuspid
When the valve is open, blood flows from atrium to ventricle.
Describe the semilunar valves
Right (pulmonary). Left (aortic).
Each cusp is shaped like a cup.
When cusps are filled, the valve is closed to stop backflow.
What are the features of arteries?
Elastic, muscular, arterioles.
Take blood away from the heart.
Contain blood under pressure.
What are the features of veins?
Large, medium, small, venules
Take blood towards the heart
Thinner walls than arteries & contain less elastic tissue and smooth muscle.
Valves to prevent backflow.
Why are capillaries important?
They are the site of exchange with tissues (interstitial fluid).
What is the tunica intima?
The innermost layer of endothelium cells surrounding an artery or vein