heart

Question 1

what is the pericardium? where is it located?

Answer 1

a fibroserous sac that enclosed the heart and roots of the great vessels. It is in middle mediastinum, posterior to body of sternum and costal cartilage 2-6

Question 2

What are the two parts of the pericardium?

Answer 2

the fibrous pericardium- outermost part; attached inferiorly to central tendon of diaphragm
the serous pericardium; the inner aspect of the pericardium, consisting of two parts

Question 3

what are the two parts of the serous pericardium?

Answer 3

parietal layer and visceral layer

Question 4

where are the parts of the pericardium located?

Answer 4

fibrous is outside
serous is core, where heart is
visceral surrounds heart
parietal is under outside layer

Question 5

what are the two pericardial sinuses:

Answer 5

oblique sinus

transverse sinus

Question 6

What kind of organ is the heart? Where is it located? What is its shape?

Answer 6

The heart is a hollow, muscular organ. It is obliquely placed in the middle mediastinum. It is irregularly conical in shape.

Question 7

What are the walls of the heart composed of? Covered with? Lined internally with?

Answer 7

The walls of the heart are composed of cardiac muscle, which make up the myocardium. The myocardium is covered externally with the epicardium, or serous pericardium and lined internally with the endocardium.

Question 8

How are the wall of the atria different from the walls of the ventricles? How are the chambers of the heart divided?

Answer 8

The atrial portion of the heart has thin walls and is divided by the atrial septum into right and left atria.
The ventricular portion of the heart has thick walls and is divided by the ventricular septum into right and left ventricles.

Question 9

What makes up the skeleton of the heart?

Answer 9

The skeleton of the heart consists of fibrous rings that surround the atrioventricular, pulmonary, and aortic orifices. It is continuous with the membranous upper part of the ventricular septum.

Question 10

What are the four surfaces of the heart? Describe them.

Answer 10

The four surfaces of the heart are:

1. Sternocostal surface – RIGHT atrium and RIGHT ventricle, separated by atrioventricular groove
2. Diaphragmatic surface – right and left ventricles, separated by posterior interventricular groove
3. Base of heart – POSTERIOR surface, formed by left atrium
4. Apex of heart – formed by left ventricle (deep to the left 5th intercostal space)

Question 11

What separates the four chambers of the heart?

Answer 11

The atria are separated from ventricles by the atrioventricular (coronary) groove.
The ventricles are separated from each other by posterior interventricular groove.

Question 12

What makes up the right atrium?

Answer 12

A main cavity and a small out-pouching (auricle). The right atrium has two parts.

Question 13

What are the two parts of the right atrium? Describe them

Answer 13

The two parts of the right atrium are:

1. Sinus venarum – smooth-walled POSTERIOR part of atrium, receives vena cavae and coronary sinus
2. Anterior part – rough-walled with musculi pectinati bundles of muscle fibers that roughen (trabeculate) the inside surface of the atrium.

Question 14

What separates the two parts of the right atrium?

Answer 14

The two parts of the atrium are separated by the sulcus terminalis and internally by a vertical edge called the crista terminalis.

Question 15

Where does right atrium receive superior and inferior vena cavae, coronary sinus and anterior cardiac vein?

Answer 15

The right atrium receives:

1. Superior vena cava – upper, posterior part
2. Inferior vena cava and coronary sinus – lower part
3. Anterior cardiac vein – anterior part

Question 16

What is the interatrial septum?

Answer 16

The posteromedial wall of the right atrium.

Question 17

What is the fossa ovalis?

Answer 17

A shallow depression on the septum that marks the site of the fetal foramen ovale

Question 18

what is the conus arteriosus?

Answer 18

The conus arteriosus is the cone-shaped superior anterior end of the right ventricle. It gives rise to the pulmonary trunk. It lies anterior to the root of the aorta and inferior to the root of the pulmonary trunk.

Question 19

Describe the inflow path of the right ventricle.

Answer 19

The right ventricle’s inflow path has irregular muscular elevations (trabeculae carnae); the moderator band crosses the ventricle from the interventricular septum to the base of the anterior papillary muscle, and carries the right branch of the atrioventricular bundle.

Question 20

Describe the outflow tract of the right ventricle.

Answer 20

The right ventricle’s outflow tract is known as the infundibulum. It is smooth-walled, directed upwards toward the pulmonary trunk, and guarded by the pulmonary valve.

Question 21

What does left atrium consist of?

Answer 21

The left atrium consists of a main cavity and a left auricle.

Question 22

How are the interior of the left atrium and the surface of the left auricle different?

Answer 22

The interior of the left atrium is smooth. The surface of the left auricle is marked with muscular ridges due to underlying pectinate muscles.

Question 23

What does the upper part of posterior wall of left atrium have?

Answer 23

It has openings of the four pulmonary veins, which bring oxygenated blood from the lungs.

Question 24

Why does septal surface of left atrium have a shallow depression?

Answer 24

The depression corresponds to the fossa ovalis of the right atrium.

Question 25

How much thicker are walls of left ventricle than of right ventricle?

Answer 25

3 times thicker

Question 26

How is the left ventricle structured?

Answer 26

It has well developed trabeculae carneae, 2 large papillary muscles, but no moderator band.

Question 27

What are the trabeculae carneae?

Answer 27

Rounded or irregular muscular columns which project from the inner surface of the right and left ventricles of the heart.