Lecture 4 Flashcards
what dies the cardiovascular system consist of?
blood vascular and lymphatic (vascular) systems
what is the blood vascular system?
a continuous loop, closed supply and drainage system
what is the lymphatic (vascular) system?
a one way system, open entry drainage system
what does the supply path consist if
only arteries
where are arteries situated and why
best to avoid damage as they are high pressure so damage could be life threatening
where do arteries change name
at each major brarnch
why do some structures often have two sources of supply
because if one gets damaged the other will still be able to supply
what is the exchange network?
capillaries of varying degrees of permeability
what is the drainage pathway and how many pathways does this consist of?
3 pathways for drainage
- deep veins
- superficial veins
- lymphatics
what is the pressure of veins like
much less pressure than arteries, same volume
where does the base of the heart sit
between ribs 2 and 3
where does the apex of the heart sit
in line with the midclavicular line and in between ribs 5 and 6
the right atrium receives ……
superior vena cava, inferior vena cava, coronary sinus
the left atrium receives ……
four pulmonary veins
where does the superior vena cava receive blood from
the head, neck, arms and chest
where does the inferior vena cava receive blood from
legs, feet, and organs in the abdomen and pelvis
what is the inner most layer of the heart wall?
endocardium = very thin layer
what does the endocardium layer contain?
- squamous epithelium (endothelium) = separates the wall from the blood
- loose irregular fibrous connective tissue = support the thin cells
- small blood vessels
- purkinje fibres
what is the biggest layer of the heart wall?
the myocardium
which ventricle has the thicker myocardium and why?
the left side because it pumps blood to the rest of the body
what is the outermost layer of the heart wall?
the epicardium = relatively thin but thicker in some places
what is the function of the pericardium?
allows the heart to beat in a lubricated sack
what are the semilunar valves
valves that control the flow from the ventricular chambers to the outflow artery, preventing blood from returning to the ventricles during filling (diastole)
when are the semilunar valves opened/closed?
pushed open as blood floes out of the heart and closed as blood starts to back flow (high pressure causes them to open)
