Module 1 Flashcards
What are the three functions of a cardiovascular system/blood?
1) Transport, 2) Homeostasis and 3) Protection
How does cardiovascular system a transport system?
Oxygen and nutrients to cells transport wastes including carbon dioxide and transports hormones (endocrine)
How does the cardiovascular system maintain homeostasis?
the change in body temperature causes the redistribution of blood, change pH levels in the blood and interstitial fluid (blood can exchange ions) and lastly control blood volume and pressure.
How does the cardiovascular system protect the body?
the cardiovascular system has white blood cells to fight infections with an immune response
What are the three major structures of the cardiovascular system?
1) Blood, 2) Heart, 3) Blood vessels
what is blood?
Blood is a fluid connective tissue that is transported through the cardiovascular system.
What is the heart?
it is a muscular organ that pumps blood throughout blood vessels to different parts of the body
What are the different types of blood vessels?
Arteries: carry blood away from the heart
Capillaries: exchange of gases, nutrients and waste products between blood and tissue (in the middle)
Vein: pumps blood towards the heart
What does the right atrium recieve?
The right artrium recieves deoxygenated blood
What does the left atrium recieve?
The left atrium recieves oxygenated blood
What is the mediastium?
The mediastium is where the heart is found - in the mediastium of the thorax - which is posterior to the lower half of the sternum offset to the left
What is the pericardium?
The pericardium is the protective fibrous sack which surrounds the heart
What are the functions of the pericardium?
The functions of the pericardium include maintaining the heart position and prevent the heart from overfilling
What are the 4 layers of the pericardium?
1) outer fibrous pericardium (loose connective tissue)
2) inner serous pericardium (fluid producing)
3) Parietal layer of serous pericardium (outer layer)
4) visceral layer of serous pericardium (the pericardial cavity is between the 2 serous layers) –> fluid –> good for lubrication
Base?
Flat floor (Aorta)
Apex?
Left inferior (pointy)
What do atriums do?
Atriums recieve blood
What do ventricles do?
pumping chambers
Draw a diagram of where deoxygenated blood goes to oxygenated blood?
Lable the diagram of te heart anterior and posterior
What is the epicardium?
the outer layer (the visceral pericardium), simple squmous epithelium + connective tissue + adipose layer
What is the myocardium?
it’s the cardiac muscle layer (majority of heart wall)
What is the endocardium?
inner layer, simple sqanous epithelium, smooth layer to minimise friction
What are intercalated disks?
Intercalated discs are sepcialised cell to cell attachment sites permitting cadiac cells to work together -> resulting in simultaneous contraction - no regeneration
Label the different atriums and ventricles
What are the differences between the left and right ventricle?
the righe ventricle pumps low pressurepulmonary circuit (thinner lumen) and left ventricle pumps for high pressure systemic circuit (thicker lumen)
What does it mean must be by unidirectional flow?
The blood must flow through each circuit before returning to the heart
What are the 2 valves that prevent backflow?
Atrioventricular valves: prevent backflow from ventricles and atria - right “tricuspid” (3 liflets) and the left “bicuspid/mitral” (2 liftlets)
The semilunar valves: to ensure no backflow into the left ventricle –> prevents backflow from pulmonary trunk and aorta into ventricles
What do papillary muscles and chordae tendinae do?
ventricular contraction produces some backflow of blood towards atria - causes the cusps to close. Papillary muscles and chordae tendinae prevent cusps from everting
What happens in ventricular systole?
It is where ventricles contract, the atrioventicular valves close (bi and tricuspid) and semilunar valves open
What happens in ventricular diastole?
It is where ventricles relax, the atrioventricular valves open and the semilunar valves close to prevent backflow
What causes the heart sounds that we associate with a heartbeat?
Heart sounds are caused by the closing of valves in the heart. The first heart sound “lubb” is caused by ventricular contraction forcing the AV valves to shut - the blood is hitting the AV valves. Then, as all chambers are in diastole, blood flows backwards in the aorta and pulmonary trunk causing the semilunar valves to close, and thus causing the second heart sound “dubb”- where the blood is hitting the semilunar valves
Label the key elements of the cardiac conduction system
—-`
Heart rate?
Heartbeats per minute
Sympathetic nervous system?
Increases heart rate
Parasympathetic nervous system?
The Vagus nerve decreases HR
Explain why the atria and ventricles do not contract simultaneously.
If this occurred, blood would simply backflow from the ventricle into the atria as the AV value would be open, which is not effective. The atria contracts with innervation from the SA node first, filling the ventricle. The AV valve closes so that when the ventricle contracts via the AV node, all blood flows into the pulmonary artery/aorta and not back into the atria
What occurs in circulation before birth?
semi O2 blood returns in the inferior vena cava, the deoxygenated blood returns in the superior vena cava (it by passes the pulmonary circuit). It detours via the oval foramen and developing interatrial septum from L to R atrium –>by passes lungs and goes to the ductus arteriosis between pulmonary trunk and descending aorta.
What occurs in the circulation after birth?
cessation of placental blood flow, the beginning of respiration decrease pressure from the lung, Ductus arteriosus closes and the foramen oval closes
