TV2001 - MSAT EXAM QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS VERIFIED GRADED A++
On the dissected specimen, describe the structure and topography of the left
heart; right heart; pericardium and middle mediastinum. What is the main
function of the left heart; right heart and pericardium?
Left heart caudally in the thorax, right heart cranially in the thorax. This position is the
original one. The human heart has rotated because of the stand-up position and the
dorso-ventral flattening of the thorax but the nomenclature being often matched with
human anatomy, we speak about left and right heart. Left heart provides the high
circulation (systemic circulation, aorta system) of the blood to the periphery and the
heart (pulmonary veins, aortic trunk) whereas right heart provides the small circulation
(pulmonary circulation, pulmonary system) to the lungs (vena cava, pulmonary trunk).
The pericardium is a two layered sac covering the heart. Serous pericardium is a thin
transparent sac, fibrous pericardium is solid whiteish sac. It is located in the middle
mediastinum and is attached to the sternum. It encloses the heart and acts as
protection/lubrication for sitting against surrounding structures. The mediastinum is
constituted by the backing of the two pleurae in the thorax; it runs along the midline from
the cranial thorax to the caudal thorax and has a cranial, middle and caudal part. It has
a mediastinal recess - which houses the accessory lobe of the right lung.
On the dissected specimen, describe the structure and topography of the cranial;
caudal aorta. What is the main function of the cranial; caudal aorta?
,The caudal aorta is a continuation of primitive aorta and runs from thorax to abdomen
under vertebrae. It provides major visceral arteries of the thorax and abdomen and ends
by the 4 iliac arteries and the median sacral artery. It is accompanied on right side by
caudal vena cava. The cranial aorta or common brachiocephalic trunk arises from the
aortic arch (primitive aorta). It gives subclavian arteries for the forelimb and common
carotid arteries for the neck and head - from bicarotid trunk; supplying oxygenated blood
to the cranial part of the body
In carnivore, rabbit, human, pig; left subclavian artery comes off independently from the
primitive aorta. In rabbit, human; left common carotid artery comes off independently
from the primitive aorta
On the dissected specimen, describe the structure and topography of the
pulmonary trunk; pulmonary veins. What is the main function of the pulmonary
trunk; pulmonary veins?
The pulmonary trunk extends from the pulmonary orifice and can be seen running on
the dorsal midline of the left side of the heart. It passes between the two auricles and
bends caudally over the base of the heart where it is joined by the ligamentum
arteriosum. After a short traject, it divides into the right and left pulmonary arteries and
is directed to the hilus of each lung with the pulmonary veins and principal bronchus;
works to send deoxygenated blood from the right heart to the lungs. Pulmonary veins
return oxygenated blood from the lungs to the left atrium. There are two clusters in the
dog, one draining the veins of each lung. In some species the veins draining the caudal
lobes of both lungs form a third cluster. The veins open variously into the roof of the left
, atrium; pulmonary veins are fixed to the pericardium and travel alongside the pulmonary
arteries
On the dissected specimen, describe the structure and topography of the cranial;
caudal vena cava. What is the main function of the cranial; caudal vena cava?
Cranial vena cava is large and extends from the entrance of the thorax and enters the
right atrium. It brings the venous blood of the high circulation to the heart. It is the
confluence of 4 large veins; two axillary veins (horses, cows) or subclavian veins
(carnivores) and two jugular veins and receives the thoracic duct and lymphatic vein.
The caudal vena cava extends from the entrance of the pelvis to the right atrium and
collects all veins of the hindlimbs, abdomen and pelvis. It begins at the entrance of the
pelvis by the confluence of 2 large common iliac veins and runs forward under the body
of the lumbar vertebrae at the right of the caudal aorta to the right atrium.
Using an opened heart, describe the structure, topography and function of the
ventricle; atrium; atrioventricular valve; papillary muscle; tendinous chordae;
trabeculae carneae). Describe the blood circulation through the heart.
Right atrium: Sinus portion (receiving both cava veins) and right auricle. Large orifices,
no valves, of the cranial and caudal cava veins. Orifices of cardiac veins. Orifice of
azygous vein. Floor almost entirely occupied by right atrioventricular orifice
Right ventricle: Two compartments, Atrioventricular/venous chamber and pulmonary
infundibulum/arterial chamber. Columns of the first order – papillary muscles. Columns
of the second order – chordae tendineae. Columns of the third order – trabeculae
corneae. Right atrioventricular orifice – tricuspid valve
Pulmonary orifice – semilunar valves
COMPLETE SOLUTIONS VERIFIED GRADED A++
On the dissected specimen, describe the structure and topography of the left
heart; right heart; pericardium and middle mediastinum. What is the main
function of the left heart; right heart and pericardium?
Left heart caudally in the thorax, right heart cranially in the thorax. This position is the
original one. The human heart has rotated because of the stand-up position and the
dorso-ventral flattening of the thorax but the nomenclature being often matched with
human anatomy, we speak about left and right heart. Left heart provides the high
circulation (systemic circulation, aorta system) of the blood to the periphery and the
heart (pulmonary veins, aortic trunk) whereas right heart provides the small circulation
(pulmonary circulation, pulmonary system) to the lungs (vena cava, pulmonary trunk).
The pericardium is a two layered sac covering the heart. Serous pericardium is a thin
transparent sac, fibrous pericardium is solid whiteish sac. It is located in the middle
mediastinum and is attached to the sternum. It encloses the heart and acts as
protection/lubrication for sitting against surrounding structures. The mediastinum is
constituted by the backing of the two pleurae in the thorax; it runs along the midline from
the cranial thorax to the caudal thorax and has a cranial, middle and caudal part. It has
a mediastinal recess - which houses the accessory lobe of the right lung.
On the dissected specimen, describe the structure and topography of the cranial;
caudal aorta. What is the main function of the cranial; caudal aorta?
,The caudal aorta is a continuation of primitive aorta and runs from thorax to abdomen
under vertebrae. It provides major visceral arteries of the thorax and abdomen and ends
by the 4 iliac arteries and the median sacral artery. It is accompanied on right side by
caudal vena cava. The cranial aorta or common brachiocephalic trunk arises from the
aortic arch (primitive aorta). It gives subclavian arteries for the forelimb and common
carotid arteries for the neck and head - from bicarotid trunk; supplying oxygenated blood
to the cranial part of the body
In carnivore, rabbit, human, pig; left subclavian artery comes off independently from the
primitive aorta. In rabbit, human; left common carotid artery comes off independently
from the primitive aorta
On the dissected specimen, describe the structure and topography of the
pulmonary trunk; pulmonary veins. What is the main function of the pulmonary
trunk; pulmonary veins?
The pulmonary trunk extends from the pulmonary orifice and can be seen running on
the dorsal midline of the left side of the heart. It passes between the two auricles and
bends caudally over the base of the heart where it is joined by the ligamentum
arteriosum. After a short traject, it divides into the right and left pulmonary arteries and
is directed to the hilus of each lung with the pulmonary veins and principal bronchus;
works to send deoxygenated blood from the right heart to the lungs. Pulmonary veins
return oxygenated blood from the lungs to the left atrium. There are two clusters in the
dog, one draining the veins of each lung. In some species the veins draining the caudal
lobes of both lungs form a third cluster. The veins open variously into the roof of the left
, atrium; pulmonary veins are fixed to the pericardium and travel alongside the pulmonary
arteries
On the dissected specimen, describe the structure and topography of the cranial;
caudal vena cava. What is the main function of the cranial; caudal vena cava?
Cranial vena cava is large and extends from the entrance of the thorax and enters the
right atrium. It brings the venous blood of the high circulation to the heart. It is the
confluence of 4 large veins; two axillary veins (horses, cows) or subclavian veins
(carnivores) and two jugular veins and receives the thoracic duct and lymphatic vein.
The caudal vena cava extends from the entrance of the pelvis to the right atrium and
collects all veins of the hindlimbs, abdomen and pelvis. It begins at the entrance of the
pelvis by the confluence of 2 large common iliac veins and runs forward under the body
of the lumbar vertebrae at the right of the caudal aorta to the right atrium.
Using an opened heart, describe the structure, topography and function of the
ventricle; atrium; atrioventricular valve; papillary muscle; tendinous chordae;
trabeculae carneae). Describe the blood circulation through the heart.
Right atrium: Sinus portion (receiving both cava veins) and right auricle. Large orifices,
no valves, of the cranial and caudal cava veins. Orifices of cardiac veins. Orifice of
azygous vein. Floor almost entirely occupied by right atrioventricular orifice
Right ventricle: Two compartments, Atrioventricular/venous chamber and pulmonary
infundibulum/arterial chamber. Columns of the first order – papillary muscles. Columns
of the second order – chordae tendineae. Columns of the third order – trabeculae
corneae. Right atrioventricular orifice – tricuspid valve
Pulmonary orifice – semilunar valves
