the circulatory system Flashcards
what are red blood cells also known as?
erythrocytes
what is the structure of red blood cells? and why?
-a biconcave shape (flattened disc shape)
-to help maximize surface area
-small and flexible so they can fit through narrow blood vessels
what is the function of red blood cells?
-to carry oxygen and carbon dioxide
-contains a protein called haemoglobin
what is the function of platelets?
-fragments of cells with protein attached to their surface
-allows them to stick together for clotting
what is the function of platelets?
to clot up to stop bleeding after illness or injury
what is the structure of plasma?
a clear, pale straw coloured liquid
-makes up the fluid component of blood
what is he circulatory system also known as?
the cardiovascular system
why is it called a double circulatory system?
it travels in two circuits
-pulmonary
-systemic
what is the structure of an artery?
thick elastic tissue in the wall
smaller lumen
what is the structure of a vein?
-less elastic tissue than arteries
-valves stop blood flowing backwards
-large lumens
what is the structure of capillaries?
-thin walls to allow gas exchange of nutrients
what are three examples of circulatory disorders?
-mitral valve (bicuspid valve) disease (MVD)
-heart murmurs
-von Willebrand disease
what does MVD cause?
-it causes the mitral valve to degenerate
-blood starts to flow backwards
-eventually worsens valves collapse causing heart failure
what are symptoms of MVD?
-heart murmur
-shortness of breath
-coughing
-reduced exercise ability
what is the treatment of MVD?
-drugs to remove excess fluid
-a low sodium diet
-exercise restrictions
what is heart murmurs caused by?
abnormal blood flow
abnormal heart structure
what are symptoms from heart murmurs?
-coughing
-weakness
-problems exercising
what are treatments of heart murmurs?
-diet
-medication
-possible surgery
what is Von Willebrand disease caused by?
-insufficient amounts of clotting factors
-there are 3 types =type1 least severe type 3 most severe
what are symptoms of Von Willebrand disease?
-unexplained bleeding
-blood in urine or faeces
-excessive bleeding from minor wounds or surgeries
-lameness in joints
what are treatments for Von Willebrand disease?
-there are no treatments available
-management involves
reducing potential for bleedings
manage bleeding that does occur
what is the systematic circuit?
carries oxygenated blood around the body and returns deoxygenated blood to the heart
what is the diastole stage?
relaxation stage
what is the systole stage?
contraction stage
what are baroreceptors?
they detect changing in pressure of blood filling the atria
what are the 4 stages of the heartbeat?
1.sinoatrial node
2.atrioventricular node
3.bundle of His
4.Purkinje fibres
what is the sinoatrial node?
the natural pacemaker
-causes an impulse causing the atria to contract forcing blood to the ventricle
-this sets the heart rhythm and rate
what is the atrioventricular node?
detects the impulse and redirects it to the bundle of His
-this causes a delay to allow the atria to contract before the ventricle
what is the bundle of His?
also called the atrioventricular bundle
-it is a group of fibres in the septum which impulse travels through to the base of the ventricles
what are the Purkinje fibres?
these fibres act as neurons and are found in the walls of the ventricles
the impulse from the bundle of His reaches the Purkinje fibres causing the ventricles to contract
