Cardiovascular System Flashcards
What does the cardiovascular system consist of?
- Heart
- Circulatory system
- Lymph, lymphatics and lymphoid organs
What does plasma contain?
- Mineral salts: sodium, chloride, bicarbonate, calcium and magnesium
- Plasma proteins: albumin, fibrinogen and clotting factors
- Metabolic components: amino acids, glucose, fatty acids, waste products like urea
What do RBCs do?
Carry oxygen bound to haemoglobin around the body
What do WBCs do?
Defend the body against pathogens
What do platelets do?
Haemostasis
What does the heart contain?
- 4 chambers: R atrium, L atrium, R ventricle, L ventricle
- 4 major blood vessels
- 4 valves
What are the 4 major blood vessels of the heart?
- Aorta
- Pulmonary artery
- Pulmonary vein
- Vena Cava
What are the atrioventricular heart valves and what do they do?
- Right valve= tricuspid valve
- Left valve= Bicuspid/Mitral valve
- Allow blood to pass from the atria to ventricles with no back flow of blood
What are the semi-lunar heart valves and what do they do?
- Pulmonic valve
- Aortic valve
-Prevent blood flowing back from arteries to ventricles
Where is ‘lub’ heard from?
Atrioventricular heart valves
Where is ‘dub’ heard from?
Semi-lunar heart valves
What is systole?
A period of contraction of the ventricles of the heart, which causes ejection of blood from ventricles to the aorta and the pulmonary trunk
What is diastole?
Heart muscles relax and this allows ventricles to fill up with blood
What is the route of blood flow through the heart regarding deoxygenated blood from the body?
- Cranial and caudal vena cava
- Right atrium
- Triscuspid valve
- Right ventricle
- Pulmonary valve
- Pulmonary artery
- Lungs
What is the route of blood flow through the heart regarding oxygenated blood form lungs?
- Pulmonary vein
- Left atrium
- Bicuspid/mitral valve
- Left ventricle
- Aortic valve
- Aorta
- Body
Describe the cardiac conduction system?
- Sinoatrial node generates an electrical impulse, which spreads through the atria causing it to contact
- Atrioventricular nodes does not conduct an impulse but provides a door to ventricles
- Impulse passes rapidly down the Bundle of His and purkinje fibres
- Both ventricles contract together starting at the apex
What is cardiac output and what is the equation?
- Volume of blood pumped by the heart per minute
- Heart rate x stroke volume
What is stroke volume?
Volume of blood ejected at each pump
What do arteries do?
Transports oxygenated blood from the heart to tissues except the pulmonary artery
What are arteries made up of and why is this beneficial?
- Thick, elastic, muscular walls
- Thickness: allows to cope with high blood pressure
- Elastic: Allows dilation and constriction
- Narrow lumen but can expand via lining folds
- Do not have valves
- Divide into arterioles
What do arterioles do?
Regulate blood flow to capillary bed
What do capillaries do?
- Link arterioles to venules
- Carry oxygenated blood, which becomes deoxygenated
What are capillaries made up of and why is this beneficial?
- Thin walls to allow diffusion
- Slow blood flow to allow diffusion
- Do not have valves
What do veins do?
Carry deoxygenated blood from the body to the heart except the pulmonary vein
