Heart + circulation

right side of heart receives what

oxygen poor blood from body tissues

left side of heart receives what

oxygenated blood from lungs

pulmonary circuit

blood vessels from heart that carry blood to and from lungs

systemic circuit

blood vessels from heart that transport blood to rest of body

atria are what chambers

receiving chambers

ventricles are what type of chambers

pumping chambers

fibrous pericardium

outer layer of dense connective tissue
adheres to diaphragm

parietal layer of serous pericardium

adheres to inner surface of fibrous pericardium
Outer layer of pericardium

visceral layer of serous pericardium

continuous with parietal layer lies on the heart and considered par of heart wall
Inner most layer (epicardium)

between parietal and visceral is the

pericardial cavity containing serous fluid

layers of heart superficial to deep

epicardium, myocardium, endocardium

what separates left and right atria

interatrial septum

what separates right and left ventricles

interventricular septum

right atrium openings

superior vena cava
inferior vena cava
coronary sinus

Trabeculae Carneae

irregular ridges of muscle in the right ventricular walls

cone shaped projections from the walls of hte heart are

papillary muscels

chordae tendineae

project superiorly from papillary muscles

blood pathway starting with right atrium

Right atrium → tricuspid → right ventricle → pulmonary valve → pulmonary artery → lungs → pulmonary veins →left atrium →bicuspid valve → left ventricle → aortic valve → aorta → artery of body→ capillaries → veins of body →superior and inferior vena cava → right atrium

valves close to prevent

backflow of blood

cardiac cycle

periods of atrial and ventriculi systole and diastole

what is thicker atria or ventricles

atria because they don’t need to do as much work gravity is on their side

visceral sensory fibers supply what organ

the heart

3 layers of blood vessels

tunica externa
tunica media
tunica intima

tunica externa

strengthens walls and anchros bessels to structures

tunica media

vasoconstriction (decrease diameter) when smooth muscles contact
vasodilate (increase diameter) when relaxed
resisting blood pressure on vessel

tunica intima

minimize friction of blood moving across

arteries move in what way

away from the heart

veins move in what way

toward the heart

what vessels has higher blood pressure

arteries

veins structure

wider lumen
thicker tunica extern
has valves
lacking elastic laminae

artery structure

thicker tunica media
walls are thicker an round shaped
contains an elastic laminae

3 types of blood vessels

arteries veins and capillaries

where are elastic arteries found

in the aorta with major branches

where are muscular arteries found

distal to the elastic arteries
(named muscular because of a thick tunica media and supply organs with blood)

arteriole

smallest artery

what is the most important blood vessel type

capillaries because they renew and refresh interstitial fluid

pericytes

spider shaped cells that has wide network that doens’t interfere with permeability

what do pericytes do

strengthen and stabilize capillaries

continuous capillaries

common: connected by tight junctions in most organs and CNS

fenestrated capillaries

span the endothelium only where there is exceptionally high exchange (small intestine, synovial membrane)

sinusoids

wide leaky capillaries containing both expanded and narrow regions

sinusoids funcction

decrease blood flow and allow for exchanges across organ wall

venules

smallest type of vein with thin tunica externa
postcapillary venules are the smallest venules

veins hold what percent of blood

65% Majority

vena cavae

tunica externa is thickened by smooth muscle and decreased elastin

valves

prevent backflow of blood

why is vein blood pressure lower

thinner walls
wider lumen
thinner tunica media
thicker tunica externa

when do arterioles become metarterioles

in capillary bends which nourish body tissues

what supplies most tissues of head external to the brain

external carotid artery

what supplies most tissues of head internal to the brain

internal corotid artery

what supplies most posterior tissues of head

vertebral artery

what does the cerebral arterial circle (circle of Willis) do

forms a loop around the pituitary gland and optic chiasms units the brains anterior and posterior blood supplies

anastomosis

proves alternate rout for blood

descending aorta two sections

thoracic and abdominal aorta