Flashcards in Lab 3 - The Heart Deck (35)
sheep and human hearts differ mainly by the shape of their...
how does the vena cava in a sheep differ to that of a human
3 major branches - L anterior, R anterior and a posterior vena cava
head-end of a human/sheep =
bottom end of a human/sheep =
the caudal end of a sheep is also known as the...
how do you know that you are looking at the ventral view of the heart?
- auricles will be pointed towards you
- ligamentum arteriosum visible
the interventricular sulcus marks the position of...
the septum and the course of one of the coronary arteries and a cardiac vein
apex formed by which ventricle?
which great artery is visible with no disection
the pulmonary trunk
how do you know that you are looking at the dorsal view of the heart?
- flat surface
- vena cava clearly visible
name of the fibrous bridge between the pulmonary trunk and the aorta
name of the first branch of the aorta
if you removed the atria and large arteries and you looked down at the four openings, which opening would be the most ventral? what would emerge in the centre? would the ventricles be more ventral or dorsal?
Pulmonary trunk is the most ventral.
Aorta would arise in the centre.
The ventricles are towards the dorsal side
How can you differentiate the auricle from the atrium?
auricle has an irregular internal surface of trabeculae whereas the main atrium is smooth. Different origins in the developing embryo.
rods of muscle fibres which cross over and weave around each other
- slender, muscular bridge which traverses the right ventricle.
- no mechanical function.
- contains purkinje fibres for conduction.
chordae tendineae when mitral valve is open and closed
loose when mitral valve is opened
tight when mitral valve is closed
how many coronary artery openings? where are they found?
2 openings found in the aorta, just inside the aortic valve flaps
where do the cardiac veins return their blood
via tiny perforations in the wall of the small left anterior vena cava
openings to the coronary arteries
which structure allows blood to cross from the right to the left atrium in the sheep fetus?
- translucent membrane ,which covers the hole in the atrial septum, in the the adult sheep
- found in the posterior vena cava
relative wall thickness:
relative wall thickness:
RV = MEDIUM
LV = THICK
RA = THIN
LA = THIN
when do the atria fill with blood?
during ventricular systole and isovolumetric relaxation
closure of the ________ and _________ valves causes the first heart sound ("____").
closure of the ________ and _________ valves causes the second heart sound ("____")
closure of the _mitral_ and _tricuspid_ valves causes the first heart sound ("_lub_").
closure of the _aortic_ and _pulmonary_ valves causes the second heart sound ("_dub_")
when are all four heart valves closed
- isovolumetric contraction
- isovolumetric relaxation
max and min pressure in the left ventricle
max = 120mmHg
min = 5mmHg
rupture of papillary muscle
- caused by myocardial infarction
- valve collapses and blood leaks onto atrium
which side of the heart is the flap covering the foramen ovale