Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Anatomy and Physiology > heart > Flashcards

heart Flashcards

1
Q

Two circuits of the heart

A

Pulmonary circuit: to lungs (rids CO2 and gets O2)

Systemic circuit: oxygenated blood to body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Heart location

A
  • in mediastinum (paricardium)
  • bt 2nd and 5th intercostal space
  • 2/3 to the left of midsternal line
  • anterior to vertebral column
  • posterior to the sternum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Base and Apex

A

Base = posterior surface towards right
Apex = inferior, left–> points towards hip
Apex pulse bt 5th and 6th ribs (mid clavicular) –> Point of Maximal Impulse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Pericardium layers

A
  • Fibrous pericardium: protects and anchors to surrounding structures and prevents overfilling
  • Serous pericardium = parietal and visceral
  • Parietal lines internal surface of fibrous pericardium
  • visceral (epicardium) on external surface of heart
  • Pericardial cavity filled with fluid to reduce friction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Pericarditis

A
  • inflammation of pericardium

- roughens membrane surfaces -> pericardial friction rub (creaking sound)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Cardiac tamponade

A

excessive fluid sometimes compresses heart

-limits pumping ability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

layers of heart wall

A

Epicardium: visceral layer of serous pericardium
Myocardium: spiral bundles of contractile cardiac muscle cells –> cardiac skeleton = interlacing CT that ancors muscle fibers, supports vessels/valves, and limits APs to specific areas)
Endocardium: continuous with endothelial lining of blood vessels –> lines heart chambers and covers cardiac skeleton of valves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

fossa ovalis

A

in interatrial septum

-remnant of foramen ovale of fetal heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Sulci

A

Coronary sulcus encircles junction of atria and ventricles
Anterior interventricular sulcus
Posterior interventricular sulcus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Auricles

A

appendages that increase atrial volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Right atrium features vs left

A

pectinate muscles in both
right has crista terminalis which separates posterior from anterior
right has tricuspid valve
left has mitral/bicuspid valve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Which blood vessels enter into each atria?

A

superior/inferior vena cava and coronary sinus empty into right
four pulmonary veins empty into left

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

location of right vs left ventricle

A

right is most of anterior surface

left is posteroinferior surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

trabeculae carneae and papillary muscle

A
  • irregular ridges of muscle on walls of ventricles

- anchor chordae tendineae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

do atria or ventricles contribute more to the pumping of the heart

A

VENTRICLES!

atria barely pump anthing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

purpose of heart valves

A
  • ensure unidirectional bloodflow

- open and close in response to pressure changes

17
Q

AV valves

A

prevent backflow when ventricles contract

chordae tendinea anchor cusps to papillary muscles and hold valve flaps in closed position

18
Q

semilunar valves

A

prevent backflow when ventricles relax

aortic and pulmonary

19
Q

Incompetent valve

A

-blood backflows so heart repumps the same blood over and over

20
Q

valvular stenosis

A

stiff flaps constrict openeing

-heart has to exert more force to pump blood

21
Q

pulmonary circuit

A 
right atrium
tricuspid valve
right ventricle
pulmonary semiluar valve
pulmonary trunk
pulmonary arteries
lungs 
pulmonary veins 
left atrium
22
Q

systemic circuit

A 
left atrium
mitral valve
left ventricle
aortic semilunar valve
aorta
tissues
23
Q

ratio of blood in systemic circulation to pulmonary circulation

A

they’re equal
pulmonary = short, low pressure
systemic = long, high friction

24
Q

coronary circulation

A
  • part of systemic circulation
  • functional blood supply to heart muscles
  • delivered when heart is relaxed
  • left ventricle receives most blood
  • has many anastosomes (junctions)
25
Q

Arteries of coronary circulation

A

Left coronary artery branches

  • anterior interventricular artery
  • circumflex artery
  • supply interventricular septum, anterior ventricular walls, left atrium, and posterior left ventricle walls

Right coronary artery branches

  • right marginal artery
  • posterior interventricular artery
  • supplie right atrium and most of right ventricle
26
Q

Angina pectoris

A

thoracic pain caused by fleeting deficiency in blood delivery to myocardium
-weakens cells

27
Q

Myocardial infarction

A
  • prolonged coronary blockage

- areas of cell death repaired with noncontractile scar tissue

28
Q

Cardiac muscle cells

A
  • short, striated, branched, fat, interconnected
  • 1-2 nuclei
  • t tubules wide and less numerous
  • SR simpler than skeletal muscle
  • 25-35% of cell volume is mitochondria
29
Q

Intercalated discs

A
  • junctions between cells, anchoring them
  • desmosomes prevent cells from separating during contraction
  • gap junctions allow ions to pass from cell to cell; electrically couple adjacent cells –> allow heart to be functional synctium
30
Q

Difference in cardiac muscle contraction from skeletal muscle contraction

A
  • 1% of cells have autorhythmicity (don’t nees NS and can depolarize entire heart)
  • All cardiomyocytes contract as a unit (all or none)
  • long absolute refractory period (250 ms) preventing tetanic contractions
  • Depolarization wave opens slow Ca channels in sarcolemma (Ca surge prolongs depolarization phase)
  • AP and contraction last longer so blood can be ejected
  • repolarization results in inactivation of Ca channels and opening of voltage K channels (Ca returns to SR)
31
Q

Similarities between cardiac muscle contractions and skeletal muscle contractions

A
  • Depolarization opens few voltage gated fast Na channels in sarcolemma (RMP foes from -90 to +30) –> close fast
  • Depolarization wave down T tubules –> SR to release Ca
  • Excitation contraction coupling occurs –> Ca binds troponin and filaments slide
32
Q

summary of electrical activity of muscle contraction

A
  1. Depolarization: fast voltage-gated Na channels open and are quickly inactivated (pos feedback)
  2. Plateau phase: Ca influx through slow Ca channels keep the cell depolarized
  3. Repolarization due to Ca channels inactivating, allowing a K efflux
33
Q

cardiac energy requirements

A

lots of mitochondria for aerobic respiration

-will switch to lactic acid from skeletal muscles if it needs a fuel source

34
Q

Does the nervous system control heart contraction?

A

Nah

BUT AND can impact heart rate

35
Q

How does the heart beat all at the same time?

A
  • Gap junctions
  • Intrinsic cardiac conduction system = network of noncontractile (autorhythmic) cells which initiate and distribute impulses
36
Q

Pacemaker cells

A
  • have unstable RMP due to slow opening of Na channels (always depolarizing)
  • @ threshold, ca channels open
  • explosive Ca influx = “rising phase” of AP
  • Repolarization = inactivation of Ca channels and opening of voltage gated K channels
37
Q

Summary of AP initiation by pacemaker cells

A
  1. Pacemaker potential –> repolarization closes K channels and opens slow Na channels, creating an ion imbalance
  2. Depolarization –> Ca channels open and a ton of Ca comes in (“rising phase”)
  3. Repolarization –> K channels open and K goes out of cell

Anatomy and Physiology (50 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions