Topic 12 Cardiovascular system Flashcards
Cardiovascular system is composed of? And what does it do?
Composed of the hear, blood vessels and blood
it transports and protects
Transports gases, nutrients, hormones, wastes and heat
proection from diseases, and fluid loss (clotting)
Describe the position of the heart in the thoracic cavity
The heart is in the area called the mediastinum which is the region between the lungs in the thoracic cavity
Mediastinum
region between lungs in the thoracic cavity/cage
this is where the heart is located
What is the coverings of the heart
coverings = pericardium
- double walled sac surrounding the heart and it has 3 layers
- a) fibrous pericardium
- b) serous pericardium
- 2 parts: parietal and visceral pericardium
- between seroud pericardial layers = pericardial cavity with serous fluid (lubricates)
identify and describe the location and structutre of the fibrous pericardium
Fibrous pericardium = wall of cavity
- outer most layer = dense irregular CT
- anchors to surrounding structures, e.g diaphragm, great vessels (aorta, vena cava etc)
identify and describe the location and structure of Parietal and visceral layers of serous pericardium
Parietal pericardium is fused to fibrous pericardium found in the serous pericardium (a layer of the heart)
- therefore fibrous + parietal pericardium = pericardial sac
**Visceral pericardium (or epicardium) **is fused to the heart surface = part of heart wall
- in the serous pericardium (a layer of the heart)
Identify and describe the location of the pericardial sac
fibrous + parietal pericardium = pericardial sac found in the serous pericardium
Idenfity and describe the location of the serous fluid and percardial cavity
Serous fluid helps with lubrication (so the walls dont stick) in the pericardial cavity between serous pericardial layers
Describe each layer of the heart wall
The heart wal has 3 parts
Epicardium
Myocardium
Endocardium
Epicardium
AKA visceral pericardium (fused to heart surface - part of heart wall)
- stratified squamous epithelium + CT (areolar)
Myocardium
Cardiac muscle
- arranged in spiral or circular patter, reinforced with CT (areolar)
Endocardium
Simple squamous epithelium + CT (areolar)
- epithelium named** endothelium **
- lines inner surface of heart and ALL blood vessles
Endothelium
The epithelium of the heart wall, Endocardium which is accompanied by Areolar CT
On the external surface of the heart, identify the 4 chambers, the anterior interventricular sulcus and the posterior interventricular sulcus
4 Chambers and assosciated blood vessels
1) right atrium
- inferior and superior vena cava
- coronary sinus (posterior)
2) left atrium
- 4 pulmonary veins
3) right ventricle
- pulmonary trunk - which then divides to form 2 pulmonary arteries
4) left ventricle
- aorta
Right atrium
inferior and superior vena cava
from upper and lower parts of body (abdominal)
coronary sinus (posterior) enlarged vein
coronary sinus
is an enlarged vein
apart of the right atrium and is posterior
left atrium contains
4 pulmonary veins
Right ventricle contains
pulmonary trunk which divides to form 2 pulmonary arteries (to rest of body)
Left ventricle contains
goes to lungs
contains the aorta
Arteries carry..?
carry blood away from the heart
veins carry..?
carry blood toward heart
What is the septa
it seperates chambers
2 types
Interatrial Septum and Interventricular septum (Interventricular sulcus)
Interatrial septum
seperates atria
Interventricular septum
Seperates ventricles
it is deep to interventricular sulcus (external), a shallow groove
interventricular sulcus
the interventricular septum is deep to the interventricular sulcus (external)
The interventricular sulcus is a shallow groove on the anterior surface of the heart
- marks the external boundary between the right and left ventricles on the anterior aspect of the heart
Sulcus
shallow groove
Identify and describe the structure and function of the primary internal strucutres of the heart including chambers, septa, valves, papillary muscles, chordae tendineae, fibrous skeleton, and venous and arterial openings
function of the chambers:
4 chambers (internal strucutres of the heart)
- 2 atriums bring blood to heart from blood vessels or veins
- 2 ventricles pump the blood from heart into arteries
Function of septa:
seperate chambers of the heart
1) interatrial septum: seperate atriums
2) interventricular septum: seperate ventricles
- the interventricular septum is deep to the interventricular suclus (shallow groove) on the anterior surface of the heart - marks external boundary between right and left ventricle
Function of valves:
includes atrioventricular valves and semilunar valves
1) atrioventricular (AV valves) invlude
- 1) biscuspid (mitral)
- left side, 2 cusps
- 2) tricuspid
- right side, 3 cusps (“its always right to tri!”)
- Chordae tendineae (CT) - attach AV valve cusps to papillary muscles (projections of the myocardium), prevent eversion of cusps (so cusps dont go into the wrong direction
2) semilunar valves (3 cusps each)
- 1) aortic - seperates left ventricle and aorta
- 2) pulmonary - seperates right ventricle and pulmonary trunk
Fibrous skeleton
contains CT fibres around muscle fibres + CT rings between atria and ventricles at the coronary sulcus (shallow groove)
- allow openings to remain open at all times (valves open and close)
- prvides electical insulation - prevents simultaneous contraction of atria and ventricles (makes sure theyre coordinated)
Fibrous skeleton contains
Connective tissue fibres that surround muscle fibres and Connective tissue rings between artia and ventricles at the coronary sulcus (shallow groove)
- allows opening to remain open at all times (valves open and close)
- provide electival insulation - prevents simultaneous contraction of the atria and ventricles
Differentiate the valves of the heart
Atrioventricular (AV) valves and semilunar valves
1) Atrioventricular valves
- 1) bicuspid (mitral): left side, 2 cusps
- 2) tricuspid: right side, 3 cusps
- Chordae tendineae (CT) - attach AV valve cusps to papillary muscles (projections of myocardium - part of heart wall; cardiac muscle), prevent eversion of cusps (so valve doesnt go in the wrong direction)
2) Semilunar valves
- 3 cusps each
- 1) aortic - seperates left ventricle and aorta
- 2) pulmonary - seperates right ventricle and pulmonary
DONT HAVE chordiae Tendineae
Chordae tendineae
CT which attach Atrioventricular valves (av) to papillary muscles (projections into the myocardium, cardiac muscle)
- prevent eversion of cusps
NOT IN SEMILUNAR VALVES
Papillary muscles
are projections of myocardium (cardiac muscle)
- the chordae tendineae attaches Av valve cusps to papillary muscles which prevents eversion of cusps
Atrioventricular valves
Has two types
Bicuspid and tricuspid
1) bicuspid: 2 valves, left side
2) tricuspid 3 valves, right side
Has Chordae Tendineae (CT) - attaches AV valve cusps to papillary muscles (projections of myocardium; cardiac muscle)
- prevents the eversion of cusps