Cardiovascular SystemBy: Kayla Sood & Cynthia Amador P.4
What is the Cardiovascular
System?
Why is the cardiovascular system important to us?
• Carries oxygen, nutrients, hormones, proteins, electrolytes, gases to cells.
• Transports toxins and carbon dioxide away from cells.
• Necessary to stay alive, duhhh!
Heart Chambers and Valves
The heart consists of 4 hallow chambers and 4 valves, that make the process of blood circulation throughout the body possible.
Heart chambers and valves(continued…)Atria- upper chambers
•thin walls
•Receives blood returning to heart
Ventricle- lower chambers
•Forces blood out heart, into arteries
Aorta- carries blood from heart to rest of body except lungs
Interatrial Septum
•Separates right and left atrium
Interventricular Septum
•Separates right and left ventricles
4 Chambers
Left atrium
•Receives oxygen rich-blood from lungs
•Pumps to left ventricle
Left ventricle
•Pumps oxygen rich-blood to aorta then out to the body
Right atrium
•Receives oxygen
•Pumps to right ventricle
Right ventricle
•Pumps oxygen poor-blood to lungs
4 Valves2 Semilunar
1.Mitral Valve (bicuspid valve) • Located on left side
2.Tricuspid Valve • Located between upper
atria and lower ventricles on right side
2 Atrioventricular
1.Aortic Valve• Located on the left side
2.Pulmonary Valve• Located in arteries leaving
the heart on right side
Purposes of the 4 major valves
Mitral and tricuspid
•Control blood flow from atria to ventricle
Aortic and pulmonary
•Control blood flow out of the ventricles
When ventricles contract, prevents back flow of blood in LA and LV
Allows blood flow from RA into RV, prevents blood moving in wrong direction
As LV contracts, opens and allows blood to leave; closes and prevents back flow of blood in LV
Prevents backflow of blood into RV and opens as it contracts
Coverings of the HeartThe heart consist of two major layers:
Heart is enclosed in a double-walled sac: pericardium
The loose fitting superficial part of this sac: fibrous pericardium.
The fibrous pericardium:
protects heart
holds together surrounding structures
prevents overfilling heart with blood
Deeper part of fibrous pericardium is the serous pericardium…
Coverings of the heart (continued…) Serous Pericardium: a thin, two-layer membrane that forms a closed
sac around the heart.
Parietal layer of serous pericardium lines internal surface of the fibrous pericardium.
At superior edges of heart, parietal layer attaches to large arteries exiting the heart.
Then turns inferiorly and continues over the external heart surface as the visceral layer, also called the epicardium,
*which is an essential part of the heart wall.
Coverings of the heart (continued…)
Layers of the Heart Wall
The heart wall is composed of three layers:
•Epicardium
•myocardium
•endocardium
Epicardium(superficial layer) is the visceral layer of the serous pericardium.
•Thin layer of CT and fat
Myocardium(middle layer) composed mainly of cardiac muscle cells (cardiomyocytes) and forms the bulk of the heart.
•CT fibers form a dense network called the fibrous cardiac skeleton that support structure of the myocardium & cardiac muscle fibers.
Inner layer: Endocardium made up of endothelial & consist of thin, smooth membrane, lines inside chambers of heart, located under myocardium.
Coverings of the heart (continued…)
Coverings of the heart (continued…)
pericardial cavity: Between the parietal and visceral layers; contains a film of serous fluid.
The serous membranes are lubricated by the serous fluid
Allows for gliding past each other, allowing the heart to work in a friction-free environment.
Blood vessels Arteries: Vessels that transports blood away form the heart & to capillaries
Capillaries: small blood vessel that connects an arteriole to a venule; thin and fragile
Veins: vessels that carry blood towards the heart
5 major vessel that go to
and leave the heart:
•Superior vena cava
•Inferior vena cava
•Pulmonary artery
•Pulmonary vein
•aorta
Blood vessels(continued…) Vena cava: veins that return deoxygenated blood
from circulation & body and empty into the right atrium• Superior: transports deoxygenated blood from upper
extremities (head, neck etc.)• Inferior: transports deoxygenated blood from lower
extremities (thorax, abdomen, etc.)
Pulmonary artery: carries deoxygenated blood from right ventricle into lungs for oxygenation.
pulmonary vein: carry oxygenated blood from lungs into left atrium; return to systemic circulation.
The aorta (largest artery): carries oxygenated blood from left ventricle of heart into systemic circulation.
*Pulmonary trunk artery: vessel in which blood from RV exits, then branches to left and right pulmonary arteries; transports blood to lungs
Blood vessels( continued…)
3 layer of blood vessels
Tunica Intima: inner most layer
•Composed of thin layers of endothelial cells
•Allows for nutrients and gas
Tunica media: muscular middle layer
•Contains smooth muscle allowing to constrict and dilate; to adjust volume of blood
Tunica extrema: outer most layer
•Surrounds tunica media
•Composed of CT
Blood Path
3. Right Atrium
4. Tricuspid Valve
5. Right Ventricle
6. Pulmonary Valve
2. Inferior Vena Cava
8. Pulmonary Veins
7. Pulmonary Artery
12. Aorta
1. Superior Vena Cava
9. Left Atrium10. Mitral
Valve11. Left Ventricle
REST OF OUR BODY!
Blood PressureThere are 5 major parts that make up the process of blood pressure:
1.Filtration• Glomerular filtration:• Fluid in blood is filtered across
capillaries of the glomerulus and into the urinary space of Bowman’s Capsule
2. Systole vs. Diastole• Systole: maximum pressure
achieved during ventricle contractions
• Diastole: Lowest pressure that remains in the arteries before the next ventricle contraction
*Both numbers make up blood pressure
Blood Pressure (continued…)
3. Pressure vs. Distance• Pressure- speed• Distance- how far blood circulates
throughout body
4. Plasma and protein relation to blood• Plasma
extracellular matrix (yellow liquid)Make up about 55% of body’s total
blood value
• ProteinsTransport of lipids, hormones,
vitamins, and metals
Blood Pressure (continued…)
5. Cardiac Output (aka Q)
Made up of 2 components:• Heart rate (HR): refers to
number of times heart beats every minute (BPM)
• Stroke volume (SV): refers to amount of blood pumped out of the left ventricle with every heart beat
• Equation for cardiac output:
HR x SV = Q
Heart Beat and Sounds• Noises created by beating heart and flow of blood
• Sounds reflect turbulence created when the heart valves snap shut
• 2 normal heart sounds “lub” & ”dub”• Lub: caused by closing of AV valves; during ventricular
systole• Dub: cause by closing of pulmonary and AV valves; during
ventricular diastole
• 2 different heart sounds S1& S2, produced by closing of AV valves and semilunar valves
• S1: caused by AV valves, Mitral and tricuspid
• S2: caused by semilunar valves, aortic and pulmonic
• Other sounds:• Murmur: when cusps don’t close completely and blood is
leaked back through valve• Aortic/pulmonic sound, mitral/tricuspid
Conduction
Conduction (continued…)
Conduction (continued…)
SA Node (Sino atrial) “pacemaker”Controls heart rateConsists of specialized cardiac
muscle fibersLocated in RA near superior vena
cavaAV Node (atrioventriclular)Part of electrical control system
of heartBetween artia and ventriclesLocated beneath endocardium
and on inferior part of septum
Conduction (continued…)
The cardiovascular system follows a very precise regulation so that an appropriate supply of oxygenated blood can be provided to different body tissues.
Conduction (continued…)
Regulation:Sympathetic nervous system: speeds up heart rateParasympathetic nervous system: slows down heart rate
Bibliographyhttps://www.boundless.com/physiology/textbooks/boundless-anatomy-and-physiology-textbook/the-cardiovascular-system-18/the-heart-172/heart-great-vessels-866-9331/
http://anatomyandphysiologyi.com/heart-anatomy/
http://www.sharecare.com/health/blood-basics/how-blood-travel-human-body
http://learn.fi.edu/learn/heart/vessels/capillaries.html
http://www.cliffsnotes.com/sciences/anatomy-and-physiology/the-cardiovascular-system/blood-vessels