Heart

Question 1

what happens to the phrenic nerves as they move towards the diaphragm

Answer 1

they become associated with the pericardium

Question 2

describe the fibrous pericardium

Answer 2

• tough CT
• blends with tunica adventitia of great vessels (sup.)
• continuous with central tendon of diaphragm (inf.)

Question 3

describe the serous pericardium

Answer 3

• line inside of fibrous pericardium (parietal)
• reflected onto heart surface (serous)

Question 4

what creates the 2 cardiac sinuses

Answer 4

arrangement of the serous pericardium

Question 5

describe the transverse sinus

Answer 5

• arises due to development from heart tube
• narrow channel between inflow and outflow tubes

Question 6

describe the oblique sinus

Answer 6

• posterior to heart
• veins of either side

Question 7

what is the ligamentum arteriosum

Answer 7

fibrous remnant of the ductus arteriosus

Question 8

what is the embryological function of the ductus arteriosus

Answer 8

allows communication between aorta and pulmonary trunk

Question 9

what nerve runs posterior to the ligamentum arteriosum

Answer 9

left recurrent laryngeal nerve

Question 10

where does the arterial supply of the heart come from

Answer 10

ascending aorta

Question 11

what are the right coronary branches of the ascending aorta

Answer 11

• SA nodal
• right marginal
• posterior interventricular
• AV nodal

Question 12

what areas do the right coronary artery branches supply

Answer 12

• R. atrium
• most R. ventricle
• SA and AV nodes
• post. 1/3 of IV septum
• part of L. ventricle

Question 13

what are the left coronary branches of the ascending aorta

Answer 13

• anterior interventricular (LAD) –> diagonal artery
• circumflex artery –> left marginal

Question 14

what areas do the left coronary artery supply

Answer 14

• L. atrium
• most of L. ventricle
• ant. 2/3 IV septum
• AV bundle
• part of R. ventricle

Question 15

Describe venous drainage of the heart

Answer 15

all veins drain to coronary sinus
EXCEPTION - anterior cardiac veins drain directly to R. atrium

Question 16

function and location of crista terminalis

Answer 16

• conducts electrical signals from SA node to AV node
• located sup. in R. atrium

Question 17

function and location of musculi pectinati

Answer 17

increase contraction in atria

Question 18

function and location of sinus venarum

Answer 18

• smooth
• R. atrium
• connects sup. and inf. vena cava

Question 19

Describe the features of the left atrium

Answer 19

• featureless
• smooth

Question 20

what type of valve is found in between the left atrium and ventricle

Answer 20

mitral valve

Question 21

what type of valve is found between the right atrium and ventricle

Answer 21

tricuspid valve

Question 22

function and location of chordae tendineae

Answer 22

• anchor atrioventricular valve
• found on ventricle wall

Question 23

function and location of papillary muscle

Answer 23

• prevent valves from opening when ventricles contract

Question 24

function and location of trabeculae carnae

Answer 24

• most likely function is to prevent suction
• muscular ridges on wall

Question 25

where are semilunar valves found

Answer 25

in the vessels

Question 26

what is the function of heart valves

Answer 26

• prevent backflow of blood

Question 27

what happens when semi lunar valves experience low pressure

Answer 27

they close

Question 28

what happens when cuspid valves experience high pressure

Answer 28

they close

Question 29

describe the fibrous skeleton of the heart

Answer 29

• support for the valves
• electrical insulation between atria and ventricles

Question 30

describe autonomic innervation of the heart

Answer 30

• from cardiac plexus to SA node

Question 31

describe parasympathetic innervation of the heart

Answer 31

• Vagus nerve
• intrinsic ganglia
• acts to decrease HR

Question 32

describe sympathetic innervation of the heart

Answer 32

• T1-5/6 spinal levels
• cervical and superior thoracic paravertebral ganglia (sympathetic chain)
• acts to increase HR