Compendium 6 - How do things get around the body Flashcards
What are the 3 main functions of the cardiovascular system?
- transport
- protection
- regulation
what does the cardiovascular system transport?
gases, nutrients, metabolic waste, (regulatory molecules, processed molecules)
What does the cardiovascular system regulate?(5)
fluid balance, pH, Body temp, Blood pressure, Exchange between blood and extracellular fluid and cells.
What are four features of the heart function
- it is a pump that generates pressure
- it routes blood (separates pulmonary and systemic circulation)
- maintains one way flow
- regulates supply
Where is the heart positioned and what protects it
it is positioned obliquely in the mediastinum in the thoracic cavity
it is protected by the rib cage, pericardial membranes and fluids
what is the structure and role of the fibrous pericardium
tough and dense connective tissue that prevents distention and anchors
what are the sulci on the heart
coronary - splits right atrium and right ventricle
Anterior interventricular - splits ventricles on anterior side
Posterior interventricular - splits ventricles on posterior side
where can you find Pericardial fat and epicardial fat
Pericardial fat - between visceral and parietal pericardium
Epicardial fat - between outer layer of myocardium and Epicardium (visceral layer of pericardium)
What are the names of the 3 layers of tissue that make up the heart (innermost to outermost) and what are they made of?
Endocardium - lines inner surface of chambers and valves, made of simple squamous epithelium
Myocardium - thick muscular layer, made of cardiac muscle cells
Epicardium - serous membrane lining outside of heart, made of simple squamous (also known as visceral pericardium)
What are pectinate muscles and what’s their role
- muscular ridges in walls of atria that allow for stretching
What are Trabeculae Carnae and what’s their role
muscle ridges in walls of ventricles that create turbulence in the blood
what are auricles and where are they found
they are extensions to increase volume that are found in the atria
what part of the heart forms the apex (most posterior and inferior)
left ventricle
what part of the heart forms the base
left atrium
what is the thickest walled chamber in the heart
Left ventricle
what causes valves to open and close
changes in pressure in the chambers
what structures prevent valves from prolabs / bulging into atria
papillary muscles and chordae tendinae
what are the 3 paths of circulation of blood from the heart
pulmonary - to lungs and back
systemic - around the body
coronary - supplies the heart
what are the 2 stages in the cardiac cycle
systole (contraction)
diastole (relaxation)
how do you calculate cardiac output
heart rate x stroke volume
what is the role of nervous and hormonal control of the cardiac system
nervous - maintains blood pressure and volume and reroutes blood
hormonal - epinephrine increases heart rate, stroke volume, vasoconstriction (in response to stress)
what makes up the cardiac conducting system
internal pacemaker and nerve like pathways in the myocardium.
outline the path of an action potential in the heart
Sinoatrial node - along atrium walls and into Atrioventricular node - travels along Atrioventricular bundles to the apex of each ventricle - along the right and left bundle branches - Purkinje fibres in ventricular walls
what are the 2 mains divisions of blood composition and at what percent,
What makes up blood plasma
55% plasma - 7% proteins
- 91% water
- 2% other solutes
45% Formed elements
