Module 4.1 - Anatomy of Heart and Vessels Flashcards
What requirements for cells are met by the circulatory system?
oxygen/nutrient supply and waste removal
What does the cardiovascular system study?
the heart, blood vessels, and blood
What are the 3 main functions of the cardiovascular system?
to transport gas, nutrients, waste throughout the body; to prevent blood loss; and fights invasion of foreign pathogens
How does the cardiovascular system prevent blood loss?
using clotting mechanisms to repair ruptured vessels
What does cardio and vascular mean mean?
heart and vessels
Shape and location of heart.
fist-sized, cone-shaped musclular organ located in the pericardial cavity in the anterior portion of the mediastinum
location of mediastinum
in middle of thoracic cavity, separates 2 plueral cavities
pleural cavities location and function
located in thoracic cavity at sides of mediastinum, each contain a lung
pericardium
thick, tough sac enclosing heart that protects it and anchors it to the diaphragm
describe the inner and outer layers of the pericardium
they are covered by a smooth layer of endothelium and between them is special fluid allows heart to slide around with little friction
myocardium
layer that contracts, bulk of the heart, composed mainly of cardiac muscle
How are myocardium muscle fibers structured?
highly branched and attached by collagen connective tissue fibers, which link all parts of the heart together
endocardium
white sheet of endothelium that lines the heart and is continuous with blood vessel linings
septum
partition between left and right set of chambers
atria
2 upper receiving chambers
ventricles
2 lowers sending chambers
What and why is there a difference in structure between the atria and ventricles?
The atria are smaller than and not as muscular as the ventricles, which must force the blood through vessels to distant parts of the body.
fossa ovalis
shallow depression on the septum separating the atria, marks the opening between atria needed by developing fetus
Why do fetus’ need foramen ovale?
so blood can pass between atrium, bypassing the undeveloped lungs, closes during birth so lungs can receive oxygen once baby is born
pulmonary valve
controls flow leaving right ventricle into pulmonary trunk
aortic valve
controls flow out of left ventricle and into aorta
Why is the aortic valve stronger than pulmonary valve?
increased blood pressure is needed to send/pump blood to entire body
mitral valve aka …
bicuspid valve, controls flow from left atrium into left ventricle
tricuspid valve
controls flow from right atrium into right ventricle
What are the 3 types of blood vessels and their functions?
arteries - send blood away from heart
veins - send blood back to heart
capillaries - exchange material with tissues
arteries
elastic, thick-walled vessels that can expand and contract to accommodate the larger blood volume flowing from the heart at the end of each heartbeat
large arteries
expand and recoil to help the heart pump blood through the systemic circulation
arterioles
Small arteries, their muscles constrict/dilate by the control of sympathetic and parasympathetic nervous system, which controls blood pressure
peripheral resitance
varying blood pressure depending on the external/internal conditions affecting the body, primarily controlled by arterioles
veins
thinner-walled vessels that return blood back to heart
what do arteries have that veins do not? Why?
palpable pulses. veins do not have pulses because they are under less pressure from the heart
veins internal valves
open towards the heart and close at end of heart beat to prevent blood from flowing backwards
veins have compliance. What is the significance?
stretch with little recoil. Because of this veins have largest amount of blood in CV system
lumen
the opening in the center of a vessel
How many layers do arteries and veins have? What are they called?
3 layers: tunica externa, tunica media, and tunica intima
What determines what layer of the vessel is thickest?
its location in the body
tunica externa aka …
adventitia. Most superficial layers, helps anchor vessel to surrounding structures
tunica media
middle muscular layer with 3 layers of its own. External elastic membrane, smooth muscle layer, and layer of internal elastic membrane
tuinca intima
innermost layer has 2 layers of its own. Subendothelial tissue layer and layer of endothelium
capillaries
narrow tubes formed from branching arterioles
capillary beds
formed from interconnected capillaries, perform exchange of materials with cells of the body
venules
small veins that collect blood from capillary beds, many join together to form a vein
What are the 2 artery systems and what do they do?
the left and right coronary arteries. Arise from base of aorta and supply heart tissue with oxygen and nutrients
location and divisions of left coronary artery
runs toward the left side of the heart and divides into theanterior interventricular branchand thecircumflex branch
anterior interventricular branch
supplies blood to both ventricles
circumflex branch
supplies the left atrium and left ventricle
generally speaking, what location is supplied by the right coronary artery?
the right atrium and ventricle
location and divisions of right coronary artery
runs toward the right side of the heart and divides into the posterior interventricular branch, right marginal artery, and atrial artery
posterior interventricular artery
on posterior/inferior of heart, supplies to both the posterior ventricles and the interventricular septum
right marginal branch
supplies to right ventricle
atrial artery
supplies the right atrium and usually supplies blood to the SA nodal artery which supplies blood to the SA node
The aortic arch turns …
postriorly and becomes the descending aorta
the descending aorta
What are the names and locations of 2 descending aorta sections?
thoracic aorta above the diaphragm and the abdominal aorta below the diaphragm
inferior vena cava
returns deoxygenated blood to heart from lower body
superior vena cava
returns deoxygenated blood to heart from upper body
brachiocephalic trunk
first branch off of the aortic arch, supplies blood to right arm and neck
what does “brachio” and “cephalic” mean?
brachio means arm and cephalic means neck
left subclavian artery
3rd branch off the aortic arch, supplies the left arm
right subclavian artery
branch off of the brachiocephalic trunk
The subclavian arteries/veins are an example of …
how major arteries/veins often have matching names when running parallel to each other
What is another name for the Circle of Willis?
cerebral arterial circle
What is the unique feature of the Circle of Willis and why is it so important?
provides alternate circulation in case of arterial blockage. Neurons need continuous supply of oxygen or they will die within minutes
vertebral arteries
rise superiorly along both sides of the spinal cord
basilar artery
from joined vertebral arteries formed at base of pons
posterior cerebral arteries
a left and right each branch off of the basilar artery
posterior communicating arteries
connect the posterior cerebral arteries to the internal coratid arteries
internal coratid arteries
arise from common coratid arteries coming up through the neck and terminate in the middle cerebral arteries
middle cerebral arteries
come off of the internal coratid arteries
anterior cerebral arteries
branches off the middle cerebral arteries
anterior communicating artery
completes the circle of circulation by connecting the anterior cerebral arteries
