The heart Flashcards
What makes up the pulmonary circuit
Pulmonary artery, arterioles, capillaries, pulmonary veins
What makes up the systemic circuit
Aorta, arteries, arterioles, capillaries , venules, systemic veins
What happens in left sided heart failure
pulmonary venous failure, pulmonary venous pressure increases
What type of blood does the right heart pump and to where
Blood without oxygen to the lungs
Low pressure is needed
What type of blood does the left heart pump and to where
Oxygenated blood to the organs
High pressure is needed
Which ventricle needs to generate a higher level of pressure
The left
Where is the systemic circuit does gaseous exchange take place
Capillaries
Why do the kidneys get around 1/5 of the total cardiac output at rest
Important to maintain homeostasis within the body
What are some landmarks for the heart with regards to other body structures
- Ventral border of the lungs
- Laterally the lungs themselves
- Cranially :thymus
- Caudally: diaphragm
How does the right ventricle sit when compared to the left ventricle
cranially
What is the coronary groove
Crown around the heart that seperates the atria from the ventricles
What are the base and the apex of the heart
Base= dorsal part formed by atria Apex= ventral part that sits on the sternum
Where does the aorta come out of the heart
middle of the base
What happens to the heart when the right side gets bigger
It moves cranially
What happens to the heart when the left side gets bigger
Moves dorsally
What is the pericardium
double-walled sac that encloses the heart
What is the role of the pericardium
prevents distension
What major vessel supplies the right atrium
The vena cava
What is the intervenous tubercle
A small projection on posterior wall of the right atrium. Said to direct blood to the atrioventricular opening
Which node is present at the junction of the right atrium and cranial vena cava
Sino-atrial node
What is the sinoatrial node
Structure that initiates electrical impulses to stimulate contraction of the heart
What is the coronary sinus
A collection of veins joined together to form a large vessel that collects blood from the myocardium of the heart
Where is the left atrium located
Top left above the left ventricle, under the tracheal bifurcation
Which veins enter the left atrium
Pulmonary veins
Where is the right ventricle located
under right atrium, wraps around. Left ventricle cranially and to the right
Where is the pulmonary artery located
Comes out of right ventricle, it is cranial and left of the aorta
Where is the left ventricle located
behind the right ventricle and to the left
forms the lateral margin of the heart
occupies all of apex
Where is the aorta located
curves upward from the left ventricle to level of sternal angle arches backward to the left and then downward
What is the right atrial valve also known as
Tricuspid valve (despite having 2 cusps in most species)
What is the left atrial valve also known as
Mitral valve
What are chordae tendinae
Filaments connecting the tips of the AV valves to the papillary muscles in the ventricles- prevents backflow of blood into the atrias
What are the cardiac valves
right and left semilunar valves regulating blood flow from ventricles into pulmonary artery and aorta
Which vessels do the right and left semilunar valves respectively regulate
Right- pulmonic
Left- aortic
What is the myocardium
heart muscle
What is epicardium
thin membrane that covers the heart
What is the endocardium
Inner layer of the heart, continuous with blood vessel lining
Describe cardiomyocytes
Large cylindircal cells that are atriated like skeletal muscle. They have short, branched fibres and a large number of mitochondria
What are intercalated discs
connecting junctions between cardiac cells
How does cardiac muscle regeneration compare to skeletal muscle
Not as effective
