Cardiovascular Part II: Heart Flashcards Preview

Z Old Anatomy > Cardiovascular Part II: Heart > Flashcards

Flashcards in Cardiovascular Part II: Heart Deck (66):

What are the two circuits of the cardiovascular system? And what does each do?

Pulmonary Circuit - transports blood between lungs and heart

Systemic Circuit - transports blood between the body tissues and the heart


What are the receiving chambers of the heart? And where does each receive blood from?


- right receives oxygen-poor blood from body

- left receives oxygen-rich blood from lungs


What are the pumping chambers of the heart? And where does each send blood to?


- right sends oxygen-poor blood to lungs via pulmonary trunk

- left sends oxygen-rich blood to body via aorta


What are the functions of the heart?

- ensure unidirectional blood flow

- pump blood to lungs and body

- develops blood pressure for nutrient and waste exchange


Describe the position and orientation of the heart.

- it is the largest organ in the mediastinum

- medial to the lungs

- obliquely positioned

- posterior to sternum

- rests on superior surface of diaphragm

- apex (anteroinferior left) in 5th intercostal space

- base is a broad posterior surface



Q image thumb

Parietal Pericardium

- the layer of serous pericardium that lines the walls of the pericardial cavity




Q image thumb

visceral pericardium

- the layer of serous pericardium that lines the outside of the heart

- AKA epicardium (when asked for "layer," not "covering")



the layer of tissue indicated by the arrow in the magnified portion of the image

Q image thumb

fibrous pericardium

- strong outer layer of dense connective tissue surrounding the serous pericardium


the heart covering formed from both layers #6 and #7

Q image thumb

serous pericardium

- "fist in a balloon" type covering

- interior of "balloon" = pericardial cavity with pericardial fluid


What are the three layers of the heart wall from outermost to innermost?

- Epicardium - visceral pericardium

- Myocardium - middle layer of cardiac muscle

- Endocardium - inner endothelium on layer of CT


How is myocardial muscle oriented and what does this achieve?

- it is a spirally-arranged network of cardiac muscles bound by connective tissue

- it produces a wringing, squeezing motion 


What are the four chambers of the heart? Which receive and which discharge blood?

Receiving Chambers:

- Right atrium

- Left atrium


Discharging Chambers:

- right ventricle

- left ventricle


Q image thumb

Right Atrium

- receives oxygen-poor blood from systemic circuit (inf. and sup. vena cava)

- contains fossa ovalis



Chamber numbered 3

Q image thumb

Left atrium

- makes up posterior surface of heart

- receives blood from lungs via pulmonary veins


chamber marked with pen

Q image thumb


right ventricle

- receives oxygen-poor blood from right atrium via right AV valve and pumps it to pulmonary trunk via pulmonary SL valve


Q image thumb

Left Ventricle

- externally forms apex of heart

- receives oxygen-rich blood from the left atrium via the left AV valve and pumps it via the aortic SL valve to the aorta

- has a thicker wall than the right ventricle because it must pump blood further, through the entire systemic circuit


# 7

Q image thumb


- known as visceral pericardium when refering to heart coverings

- most superficial layer of the heart 

- lubricates heart 



Q image thumb


- middle layer of cardiac muscle in heart wall

- thickest layer of heart

- arranged spirally to contract in a wringing motion



Q image thumb


- deepest layer of heart

- lines inner surface

- made up of endothelial & connective tissues


Incoming Vessels of the Heart

Right Atrium (oxygen-poor)

- superior vena cava

- inferior vena cava

- coronary sinus

Left Atrium (oxygen-rich)

- pulmonary veins (4 total, 2 L & 2 R)


Outgoing Vessels of the Heart

Right Ventricle ----> Pulmonary Trunk

Left Ventricle ------> Aorta


Q image thumb

fossa ovalis

- oval depression in interatrial septum

- vestige of the fetal foramen ovale, a bypass of the pulmonary circuit


green area

Q image thumb

interventricular septum

- wall between the two ventricles


indicated by green line

Q image thumb


- inferior conical end of heart formed by exterior of inferior left ventricle


the posterior face of the heart

Q image thumb


- broad posterosuperior surface of heart

- primarily formed by left atrium


area circled in green

Q image thumb

right auricle

- wrinkled, flaplike extension of right atrium



Q image thumb

left auricle

- wrinkled extension of left atria


What are the two different kinds of valves in the heart and what are their functions?

atrioventricular valves

- between atria and ventricles

- bicuspid on left, tricuspid on right

semilunar valves

- between ventricles and arteries (one pulmonary, one aortic)

- 3 pocket-like ("half-moon") cusps


- both serve to allow only unidirectional flow of blood



Q image thumb

Mitral Valve (AKA bicuspid valve)

- left atrioventricular valve



Q image thumb

Tricuspid Valve

- right atrioventricular valve



pulmonary semilunar valve

- between right ventricle and pulmonary trunk



Q image thumb

aortic semilunar valve

- between left ventricle and aorta


What are the cusps of cardiac valves made of?

- they are flaps of endocardium over a core of dense CT


white fibers shown here:

Q image thumb

Chordae Tendineae

- thin strands of collagen fibers connecting cusps of AV valves to papillary muscles

- prevents the valves from everting into the atria



Q image thumb

papillary muscles

- cone-shaped muscular projections from the walls of the ventricles which anchor chordae tedineae



Q image thumb


- largest artery in the body

- accepts blood from left ventricle



Q image thumb

Pulmonary Trunk

- anterior to aorta

- divides into left and right pulmonary arteries

- accepts blood from right ventricle


#2 and #6

Q image thumb

Pulmonary Veins

- enter left atrium from lungs

- two sets of two, left and right



Q image thumb

superior vena cava

- large posterosuperior vein

- returns blood from head, neck and upper extremities

- enters right atrium of heart




Q image thumb

inferior vena cava

- returns blood from abdomen and lower extremities

- enters right atrium


Cardiac Muscle

- forms middle layer of heart called myocardium

- striated

- contracts via sliding filament mechanism, similar to skeletal muscle

- involuntary

- contracts to pump blood through heart and into vessels


Cardiac Muscle Cell Characteristics

- short (unlike skeletal muscle)

- branching

- 1-2 central nuclei

- not fused colonies


Q image thumb

intercalated disks

- complex junctions between cardiac muscle cells

- interlocking of adjacent sarcolemmas (muscle cell membranes)

- have cell junctions: adhering and gap junctions


What is a cardiac muscle "fiber"?

Multiple short cardiac muscle cells lined up and connected by intercalated discs

(unlike skeletal muscle fibers which are a single, long muscle cell)


What separates different cardiac muscle fibers?


- connective tissue with blood vessels and nerves

- binds adjacent cardiac fibers, but seperates their cells


How do most cardiac muscle cells receive contraction signals?

- most are NOT innervated

- they receive signals through gap junctions of intercalated disks


What are the specialized cells that conduct electrical impulses through the heart?

Conduction System Cells

- specialized cardiac muscle cells

- cause chambers to contract in the proper sequence



- a property of cardiac muscle cells

- rhythmic activity without being driven by rhythmic external stimulation


area from which signals are spreading here:

Q image thumb

- sinoatrial node - 

- specialized cardiomyocytes

- in the superior wall of right atrium

- sets inherent rate of contraction 

- impulses spread to the atria



Q image thumb

atrioventricular node

- in inferior wall of interatrial septum

- electrically connects atrial and ventricular chambers




Q image thumb

Atrioventricular Bundle (AKA Bundle of His)

- collection of heart muscle cells specialized to conduct impulses from the AV node to the bundle branches and Perkinje fibers which stimulate ventricular contraction 



Q image thumb

- left and right bundle branches

- branches of the AV bundle which conduct impulses to the left and right ventricles


rounder, emptier cells in center of image

Q image thumb

Purkinje fibers

- specialized conductive fibers in ventricular walls

- larger size makes for easier ion flow & signal conduction

- bigger, emptier-looking cells among normal cardiac muscle cells


A image thumb

Cardiac Innervation (which nerves?)

- rate altered by external controls

Nerves to Heart:

  • Vagus nerve (parasympathetic branch)
  • Sympathetic fibers (from cervical and upper thoracic chain ganglia)
  • Visceral sensory fibers



red vessel indicated by arrow

Q image thumb

left coronary artery

- splits into:

  • anterior interventricular artery
  • circumflex artery
  • posterior interventricular artery


general term for all vessels shown here in red

Q image thumb

coronary arteries

- vessels which supply blood to the myocardium

- arise from the aorta


part B

Q image thumb

coronary sinus

- largest coronary vein

- where blood re-enters right atrium from coronary circulation


Q image thumb

anterior interventricular artery


Q image thumb

circumflex artery



Q image thumb

posterior interventricular artery




Q image thumb

right coronary artery

- leads to right marginal artery at bottom of right ventricle



Q image thumb

marginal artery

- branches off of right coronary artery


blue vessel here:

Q image thumb

great cardiac vein

- vein that runs along anterior surface of heart between ventricles (along with anterior interventricular artery)


middle cardiac vein

Q image thumb

middle cardiac vein

- runs along posterior heart between ventricles 

- paired with posterior interventricular artery


part G

Q image thumb

internodal pathway

- carries signals from the sinoatrial to atrioventricular nodes of the cardiac conduction system