Internal Features of the Heart

Question 1

Right atrium

Answer 1

Description: forms the right margin of the heart
Notes: receives deoxygenated blood from the SVC, IVC, and coronary sinus

Question 2

Auricle of the right atrium

Answer 2

Description: pouch-like appendage projecting anteriorly from the atrium

Question 3

Pectinate mm. of the right atrium

Answer 3

Description: ridges of cardiac muscle located in walls and auricle of the right atrium

Question 4

Crista terminalis of the right atrium

Answer 4

Description: ridge of cardiac muscle separating smooth wall of the posterior atrium from rough wall of the anterior atrium
Notes: extends from opening of the SVC above to opening of IVC below

Question 5

Opening of the SVC

Answer 5

opening in the roof of the atrium

Question 6

Opening of the IVC

Answer 6

opening in the floor of the atrium

Question 7

Opening of the coronary sinus

Answer 7

located medial to opening of IVC

Question 8

Fossa Ovalis

Answer 8

Depression in interatrial septum of right atrium

Remnant of foramen ovale that connected the right and left atria in the fetus

Question 9

Right Ventricle

Answer 9

Forms most of the anterior surface of the heart and inferior border in anatomic position
Receives blood from right atrium; pumps blood into pulmonary trunk

Question 10

Tricuspid valve

Answer 10

Between the right atrium and right ventricle
Also called the right atrioventricular (AV) valve; open when ventricle is relaxed (diastole); closed when ventricle contracts (systole)

Question 11

Papillary mm. of right ventricle

Answer 11

Cone-shaped muscular projections attached to walls of the ventricle
Attach to cusps of tricuspid valve via chordae tendinae

Question 12

Chordae tendinae of right ventricle

Answer 12

Thin, tendionous cords that attach cusps of tricuspid valve to papillary mm.
Prevent cusps from prolapsing into atrium when ventricle contracts

Question 13

Trabeculae carnae of right ventricle

Answer 13

Ridges of cardiac muscle lining the wall of the ventricle

Question 14

Septomarginal trabeculae

Answer 14

Ridge of cardiac muscle stretching from interventricular septum to anterior papillary m. in right ventricle
Also called the ‘moderator band’; contains part of right branch of the atrioventricular bundle

Question 15

Conus arteriosus (Infundibulum)

Answer 15

Smooth area of right ventricle leading to the pulmonary trunk

Question 16

Pulmonary valve

Answer 16

Located at the base of the pulmonary trunk

Opens when the ventricle contracts (systole); closed when the ventricle is relaxed (diastole)

Question 17

Interventricular septum

Answer 17

Partition between the left and right ventricles

Has membranous and muscular parts

Question 18

Left atrium

Answer 18

Forms most of the base (posterior surface) of the heart

Receives oxygenated blood from pulmonary circulation

Question 19

Auricle of the left atrium

Answer 19

pouch-like appendage projecting anteriorly from the atrium

Question 20

Pectinate mm. of the left atrium

Answer 20

Ridges of cardiac located in the auricle of the left atrium

Question 21

Openings of pulmonary veins

Answer 21

Superior and inferior openings on both the right and left side of the posterior wall

Question 22

Left Ventricle

Answer 22

Forms nearly all of the left border and apex of the heart, and most of the diaphragmatic surface
Receives blood from left atrium; pumps blood into ascending aorta

Question 23

Mitral valve

Answer 23

Between the left atrium and left ventricle
Also called the bicuspid or left atroventricular (AV) valve; open when ventricle is relaxed (diastole); closed when ventricle contracts (systole)

Question 24

Chordae tendinae of left ventricle

Answer 24

Thin, tendinous cords that attach cusps of mitral valve to papillary mm.
Prevent cusps from prolapsing into atrium when ventricle contracts

Question 25

Interventricular septum

Answer 25

Partition between the left and right ventricles

Has membranous and muscular parts

Question 26

Papillary mm. of the left ventricle

Answer 26

Cone-shaped muscular projections attached to walls of the ventricle
Attach to cusp of mitral valve via chordae tendinae

Question 27

Trabeculae carnae

Answer 27

Ridges of cardiac muscle lining the wall of the ventricle

Question 28

Aortic valve

Answer 28

Located at the base of the ascending aorta

Open when the ventricle contracts (systole); closed when the ventricle is relaxed (diastole)