cardiovascular system Flashcards
what makes up 55% of blood
plasma
what is plasma made up of
mostly water and proteins
3 major proteins in plasma
- albumin - prevents water diffusing out of bloodstream
- globulins - immunoglobulins are antibodies and other transport globulins carry lipids and minerals
- fibrinogen - involved in cascade of events for blood clotting
what makes up less than 1% of blood
platelets and leukocytes in the buffy coat
5 types of leukocytes and their abundance
- neutrophils 50-70%
- lymphocytes 25-45%
- monocytes - 3-8%
- eosinophils - 2-4%
- basophils - 0.5-1%
diapedesis
changing shape and leaving the bloodstream (what leukocytes do)
2 types of WBC
- granuloctyes (neutrophils, eosinophils, basophils)
2. agranuloctyes (monocytes, lymphocytes)
thrombocytes
platelets- break off larger cell called megakaryocyte - form platelet plug in area of damage and trap red blood cells in fibrin strands
what is blood serum and how is it formed
blood with all the formed components removed, forms when blood sits for a long time - coagulates and forms blood clot trapping all the formed elements
location of heart
in the mediastinum, between the lungs, angled to the left with 2/3 of the heart on the left of the median plane (apex lies to the left)
costal cartilage of 3rd rib joining to the sternum
anterior right point of the heart
costal cartilage of the 6th rib fingerwidth lateral to the sternum
inferior right point of the heart
cartilage of the 2nd rib a little lateral to the sternum
superior left point of the heart
in the 5th intercostal space on imaginary line that extends inferiorly from the
inferior left point of the heart
list the coverings of the heart in order from most superficial to deep
- fibrous pericardium
2. serous pericardium (2nd and 3rd layer)
what prevents the heart from overfilling
the fibrous pericardium
what is the serous pericardium made up of
- parietal peridcardium - overlays epicardium
- visceral perdicardium - is the epicardium
these 2 layers are continuous with each other
pericardial cavity b/w them - containing pericardial fluid
3 layers of the heart wall from most superficial to most deep
- epicardium - visceral layer of the serous pericardium, often infiltrated w fat in older people
- myocardium - cardiac muscle arranged in a spiral pattern allows proper ejection of blood into vessels from apex to base
- endocardium - a thin layer of connective tissue with simple squamous epithelium
interventricular septum
divides the left and right ventricles
interatrial septum
divides the left and right atria
2 main grooves that indicate the boundaries of the heart chamber
- coronary sulcus - around atria and ventricles
2. interventricular sulcus (posterior and anterior)
tricuspid valve
b/w right atrium and right ventricle
what 3 veins does the right atrium receive blood from
- superior vena cava
- inferior vena cava
- coronary sinus
2 parts of the right atrium
- posterior with smooth walls
2. anterior with horizontal ridges (pectinate muscles)
the important landmark for sites of veins entering the right atrium separating the anterior and posterior parts of the right atrium
crista terminalis
depression in the interatrial septum marking previous opening in the fetal heart
fossa ovalis of the right atrium
bicuspid or mitral valve
b/w left atrium and ventricle
characteristics of the left atrium
mostly smooth walled, pectinate muscles only exist on the lining of the left auricle
auricle
small flap shaped like dog’s ear projecting anteriorly from both atriums
what 2 veins does the left atrium receive blood from
- left pulmonary vein
2. right pulmonary vein
internal characteristics of the right ventricle
- trabeculae carneae - walls lined with irregular ridges
- papillary muscles attached to flaps of tricuspid via chordae tendineae
- pulmonary semilunar valve - opening b/w the right ventricle and pulmonary trunk
internal characteristics of the left ventricle
- trabeculae carneae - walls lined with irregular ridges
- papillary muscles attached to the flaps of bicuspid via chordae tendineae
- aortic semilunar valve - opening b/w left ventricle and aorta
4 functions of the fibrous skeleton of the heart
- anchorage of valve cusps
- prevention of overdilation of valve openings
- insertion of cardiac muscle
- blockage of direct spread of electrical impulses that originate in the right atrial region from being able to travel directly through the atria down to the ventricles
what is the sound of closing of the AV valves at the start of ventricular contraction?
lub
what is the sound of the closing of semilunar valves at the end of ventricular contraction
dub
how to listen to the aortic valve
superior right corner in the 2d intercostal space at right sternal margin
how to listen to the pulmonary valve
superior left corner in the 2nd intercostal space at the left sternal margin
how to listen to the tricuspid valve
inferior right corner the 5th intercostal space in the right sternal margin
how to listen to the mitral/bicuspid valve
inferior left corner of heart apex 5th intercostal space in line with the middle of the clavicle
three layers of blood vessel wall (deep to superficial)
- tunica intima - contains endothelium (simple squamous epithelial cells)
- tunica media - circular smooth muscle with elastin and collagen fibrils
- tunica externa - layer of connective tissue that run longitudinally (collagen and elastin)
what are elastic (conducting) arteries
large, close to the heart
large lumen for least resistance
more elastin to control BP surges
what are muscular (distributing) arteries
supply organs and organ groups
thicker tunica media
can change diameter
what are arterioles
smallest arteries
tunica media has only one or 2 layers
diameter can also be regulated
