Cardiovascular System; Heart and Blood Vessels Flashcards
What is the Heart?
Muscular double pump, generating the force to pump blood through the body/lungs. Provides a one-way system for blood.
What are Diastole and Systole’s?
Diastole is the filling of the ventricles while Systole is the contraction of the muscle upwards, pumping/emptying the blood into the ventricles
Which coronary vessel supplies cardiac muscle blood?
Aortic Ostia
What are the main vessels of coronary arteries?
Main Vessels; Right Coronary Artery and Left Coronary Artery which splits into left anterior descending artery and circumflex artery
2 Parts to Cardiac Muscle + What’s a tamponade?
Outer layer - Pericardium which protects and lubricates to reduce friction damage. Tamponade - air/fluid fills the pericardium layer. Myocardium - Heart Muscle
3 Types of Myocardium Cell
-Cardiac Fibres - Involved in contraction (muscle pump) + Mechanical which requires electrical stimulation
-Nodal
-Conducting - for the transmission of action potential (electrical impulse)
What do Nodal cells divide into?
Automaticity - the ability to spontaneously generate and discharge an electrical impulse
Rhythmicity - the ability to maintain a stable, repetitive depolarisation and repolarisation within the cardiac muscle
What are the Functions of Cardiovascular System?
- Carrying O2 to cells & remove cell waste
- Collect nutrients from intestine
- Carry white blood cells to aid immune response
- Generate/maintain blood pressure that helps these processes
Cardiac Output Calculation
Cardiac Output = Stroke Vol x Heart Rate
Blood Pressure Calculation
Blood Pressure = Cardiac Output x Systemic Vascular Resistance
Cardiac Output Definition
quantity of blood ejected by the left ventricle each minute (litres per min)
Stroke Volume Definition
quantity of blood ejected into the systemic, usually related to the force of ventricular contraction
How is an Aortic Aneurysm’s Created?
Something interrupts the tunica interna layer e.g. no longer smooth/damaged. The turbulence/current created chips away at each layer creating a bulger of blood causing an increase in pressure till it bursts
What causes Aortic Aneurysm’s?
Large amounts of adrenaline, cholesterol/fat build up
2 Types of Aortic Aneurysm’s
Thoracic or Abdominal
Functions of the Blood Vessels
Arteries - carry blood away from the heart into arterioles Arterioles - Branches of arteries to control flow to capillaries Veins - carry deoxygenated blood from capillaries back to heart Capillaries - carry blood straight to cells, to diffuse with cell fluid to exchange materials with tissues
Functions to Different Parts to Blood Vessels
- Tough Fibrous Outer Layer - Withstands high pressure
- Muscle - Contracts to control blood flow
- Elastic - Stretches and recoils back to maintain blood pressure
- Endothelium - thin for diffusion
- Lumen - Central cavity in which blood flows
Structure Relating to Function; Artery
Thickest Muscle - contracts to control blood flow
Thick Elastic - Stretches for recoil to maintain high pressure
Thick Wall - Withstand high pressure
No Valves - blood doesn’t flow backwards
Structure Relating to Function; Arterioles
Thicker Muscles - muscle contracts to reduce flow of blood in lumen to control the blood supply to capillaries Thinner Elastic - to reduce pressure
Structure Relating to Function; Vein
Thinner Muscle - carry blood away therefore don’t need high pressure
Thin Elastic - low pressure so too low for recoil Thinner Wall - lower pressure, allow flattening to air blood flow Valves - Ensure blood doesn’t flow backwards and goes to heart
Structure Relating to Function; Capillary
1 Cell Thick - short diffusion pathway to tissue fluid
Narrow Diameter- Never far from tissue for diffusion
Narrow Lumen - Brings blood closer to tissue fluid for material exchange
Spaces between lining (Endothelial cells) - Allow white blood cells to escape to deal with infections
Where Percentages of Blood are in each Part of the Body?
Pulmonary =12%
Heart =8%
Arteries = 15%
Capillaries =5%
Veins =60%
