Lab 1 SCB 204 Lagcc

3 sets combined

Which chamber receives deoxygenated blood before it is pumped into the pulmonary circulation?

Right atrium

Which valve with two cusps prevents backflow of oxygenated blood into the left atrium during left ventricular contraction?

Bicuspid (mitral) valve

Which chamber is responsible for pumping oxygenated blood into the aorta?

left ventricle

what are the muscular projections inside the ventricles that help secure the atrioventricular valves?

papillary muscles

which vessel receives deoxygenated blood from the right ventricle to carry it toward the lungs?

pulmonary trunk

Which intermediate muscular layer of the heart wall is responsible for contraction?

Myocardium

What is the muscular wall that separates the right and left ventricles?

interventricular septum

Which valve with three cusps is located between the right ventricle and the pulmonary trunk?

pulmonary semilunar valve

Which valve prevents the backflow of blood into the right atrium during right ventricular contraction?

tricuspid valve

What fibrous, thread-like structures anchor the AV valve cusps to the papillary muscles?

chordae tendineae

What is the percentage of pacemaker cells in cardiac myocytes?

1%

What is the percentage of contractile cells in cardiac myocytes?

99%

What is the primary function of pacemaker cells?

spontaneously and rhythmically generates action potentials to set the pace of the heart

What is the primary function of contractile cells?

depolarize in response to pacemaker action potentials and contract to pump blood

What are the three populations of the cardiac conduction system?

1. Sinoatrial (SA) node

2. Atrioventricular (AV) node

3. Purkinje fiber system

Where is the Sinoatrial (SA) node located?

upper right atrium

What is the intrinsic rate of depolarization of the SA node?

60 times per minute or more

What is the normal pacemaker of the heart?

Sinoatrial (SA) node

What is the anatomical location of the Atrioventricular (AV) node

posterior and medial to the tricuspid valve

What is the intrinsic rate of depolarization of the AV node?

40 times per minute

What are the components of the Purkinje fiber system in order of the signal flow?

1. Atrioventricular bundle

2. right and left bundle branches

3. terminal branches

What is the intrinsic rate of depolarization of the Purkinje fiber system?

20 times per minute

Explain the path of the Atrioventricular bundle

Penetrates the heart’s fibrous skeleton in the inferior interatrial septum and superior interventricular septum

explain the path of the right and left bundle branches

course along the right and left sides of the interventricular septum toward the apex

What is the function and endpoint of terminal purkinje fibers?

spread from the apex to penetrate ventricles and directly contact ventricular contractile cardiac muscle cells

What is step 1 in action potential propagation?

The SA node generates an action potential that spreads through atrial contractile myocytes via gap junctions

What is step 2 in action potential propagation?

Atrial contractile cells depolarize and contract, while the signal travels to the AV node

What is step 3 in action potential propagation?

signal reaches the AV node, where conduction slows slightly to allow ventricles to fill with blood

what is step 4 in action potential propagation?

the signal travels through the AV bundle, crossing the fibrous skeleton into the interventricular septum

what is step 5 in action potential propagation?

the signal splits into the right and left bundle branches, descending along the septum toward the apex

what is step 6 in action potential propagation?

terminal Purkinje fibers conduct the action potential rapidly upward through the ventricular wall muscle

what is step 7 in action potential propagation?

ventricular contractile cells depolarize and contract in unison, pumping blood to the lungs and body

what mechanism allows fast electrical speed between cardiac cells?

gap junctions within intercalated discs

what is the functional purpose of the AV nodal delay?

allows the atria to complete contraction and fill the ventricles before ventricular contraction begins

what is the direction of ventricular depolarization vector?

spreads from the apex upward through the ventricular walls toward the base

Name structure 1

Left common carotid artery

name structure 2

Left subclavian artery

name the structure 3

Ligamentum arteriosum

name the structure 4

Left pulmonary artery

name the structure 5

Pulmonary veins

name the structure 6

Left atrium

name the structure 7

left auricle

name the structure (8)

left coronary artery

name the structure (9)

Great cardiac vein

name the structure (10)

Anterior interventricular artery

name the structure (11)

Right auricle

name the structure (12)

right atrium

name the structure (13)

Right coronary artery

name the structure (14)

Pulmonary trunk

name the structure (15)

Ascending aorta

name the structure (16)

Superior vena cava

name the structure (17)

Right pulmonary artery

name the structure (18)

Aortic arch

name the structure (19)

Brachiocephalic veins

name the structure (20)

Brachiocephalic trunk

name the structure (21)

Descending thoracic aorta

name the structure (22)

Pulmonary veins

name the structure (23)

Inferior vena cava

name the structure (24)

Coronary sinus

name the structure (25)

Posterior interventricular artery

name the structure (26)

Middle cardiac vein

name the structure (27)

Circumflex artery

Name the structure (28)

Great cardiac vein

name the structure (1)

Right auricle

name the structure (2)

Pectinate muscles

name the structure (3)

Sinoatrial node

name the structure (4)

Right atrium

name the structure (5)

Fossa ovalis

name the structure (6)

Atrioventricular node

name the structure (1)

Right ventricle

name the structure (2)

Left ventricle

name the structure (3)

Trabecule carneae

name the structure (1)

Chordae tendineae

name the structure (2)

Papillary muscle

name the structure (1)

Pulmonary valve

name the structure (2)

Tricuspid valve

name the structure (3)

Chordae tendineae

name the structure (4)

Papillary muscle

name the structure (5)

Bicuspid valve

Name the structure (6)

Chordae tendineae

name the structure (7)

Aortic valve

name the structure (1)

Right branch of bundle of His

name the structure (2)

Purkinje fibers

name the structure (3)

Left branch of bundle of His