Exam 2

Question 1

Be able to identify important thoracic muscles.

Answer 1

Pectoralis major
Pectoralis minor
Trapezius
Latissimus dorsi

Question 2

Be able to identify skeletal structures of the thorax.

Answer 2

Sternum (manubrium, body, sternal angle, xiphoid process)
Ribs (true, false, floating)
Scapula

Question 3

Be able to identify respiratory structures.

Answer 3

Trachea (right main bronchus, left main bronchus)
Right lung (3 lobes)
Left lung (2 lobes)

Question 4

Be able to identify structures in the root of the lung.

Answer 4

Pulmonary trunk, AKA main pulmonary artery (bring deoxygenated blood to lungs)
Pulmonary veins (return oxygenated blood)
Bronchi (connect lungs and trachea)

Question 5

What does the autonomic nervous system innervate?

Answer 5

Cardiac muscle, smooth muscle and glands

Question 6

What divisions of the autonomic nervous system are associated with the respiratory system?

Answer 6

Parasympathetic “rest and digest”
* bronchoconstriction
* vasodilation
* secretion

Sympathetic “fight or flight”
* bronchodilation
* vasoconstriction
* inhibit secretion

Question 7

Describe the chambers of the human heart.

Answer 7

2 atria (top)
2 ventricles (bottom)

R side: receive and pump deoxygenated blood
L side: receive and pump oxygenated blood

Question 8

Be able to identify structures of the right atrium.

Answer 8

R atrium receives deoxygenated blood from the heart.

superior vena cava blood from upper body
inferior vena cava blood from lower body
right atrioventricular (tricuspid valve) 3 flaps that separate atrium/ventricle

Question 9

Be able to identify structures of the right ventricle.

Answer 9

R ventricle pumps deoxygenated blood to the lungs.

chordae tendinae straps papillary muscles/flaps
papillary muscles
interventricular septum separate R/L ventricle
pulmonary semilunar valve
pulmonary trunk send deox blood to lungs

Question 10

Be able to identify structures of the left atrium.

Answer 10

L atrium receives oxygenated blood from the lungs.

pulmonary veins carry ox blood from lungs
left atrioventricular (mitral valve) 2 flaps that separate atrium/ventricle

Question 11

Be able to identify structures of the left ventricle.

Answer 11

L ventricle pumps oxygenated blood to the body.

papillary muscles
chordae tendinae
aortic semilunar valve

Question 12

Be able to identify the coronary arteries.

Answer 12

Oxygenated blood first goes into the coronary artery, since the heart must take care of itself first.
Left main coronary artery
anterior interventricular artery (LAD) “widowmaker” bc supply L ventricle
circumflex branch of left coronary artery supply L. atrium

Right main coronary artery
right marginal branch of R. coronary artery supply R. atrium and SA node (sinoatrial “pacemaker”)
posterior interventricular branch of right coronary artery supply both ventricles

Question 13

Be able to identify structures of the great vessels.

Answer 13

aortic arch umbrella handle
brachiocephalic a.
subclavian a.

Question 14

Describe the microscopic components of blood.

Answer 14

Blood is connective tissue.

plasma liquid part of blood (makes up 55%) with important proteins (albumin, globulins, fibrinogen)
erythrocytes (RBCs) transport oxygen and CO2
leukocytes (WBCs) immune cells
thrombocytes (platelets) blood clotting (not technically cells)

Question 15

In hollow organs, what are the 2 possible outermost layers?

Answer 15

adventitia present in organs surrounded by ONLY connective tissue
(ex- surrounding blood vessels)

serosa present in organ surrounded with connective tissue AND epithelium
(ex- surrounds heart, lungs, digestive organs)

Question 16

Describe the organization of layered heart tissues.

Answer 16

1. endocardium
endothelium, connective tissue

subendocardial conducting network via purkinje fibers

2. myocardium
cardiomyocytes connected via intercalated discs
endomysium (conn. tissue that supply cardiomyocytes)

3. epicardium “visceral pericardium”
subepicardial connective tissue, mesothelium

Question 17

Describe the structure of a cardiomyocyte.

Answer 17

striated
short, branched
1-2 nuclei per cell
connected via intercalated discs

Question 18

Describe the features and functions of an intercalated disc.

Answer 18

Intercalated discs are specialized complexes b/w cardiomyocytes.

have:
Gap junctions allow flow of Ca2+
fascia adherens staple cells together

Question 19

Describe organization of blood vessel layers.

Answer 19

In descending order:
1. tunica externa (-adventitia) thickest in VEINS
vasa vasorum contains small vessels/nerves in L-sized vessels

external elastic membrane in M-sized a.
2. tunica media muscular
smooth muscle (thicker in a. )

3. tunica intima
internal elastic membrane in M-sized a.
subendothelial connective tissue basement membrane
endothelium (simple squamous) lines entire CV system including blood vessels and lymph channels

Question 20

Compare and contrast different blood vessel types.

Answer 20

1. arteries carry blood away from heart
elastic a. largest and near heart, contain vasa vasorum
muscular a. M-sized, have thickest tunica media, most named a. are muscular
arterioles smallest, 1-2 smooth muscle layers, for BP regulation

2. capillaries are the smallest blood vessels in the body, RBCs travel single-file, for nutrient/gas exchange
continuous c. most common but least permeable
fenestrated c. more permeable (have pores) in their endothelium, incr. filtration (found in kidneys and s. intestine)
sinusoid c. most permeable (have wide gaps) in liver

3. veins large structures with valves and sometimes vaso vasorum that carry blood towards the heart
venules smallest venous vessles with thin media/externa layer

Question 21

Describe the parts and function of the lymphatic system.

Answer 21

The lymphatic system collects leaked fluid from blood vessels (interstitial fluid), filters via lymph nodes and returns to veins.

lymphatic capillaries smallest lymph vessels that collect fluid, single layer of endothelial cells
lymph interstitial fluid after it has been collected in lymph c.
lymphatic c -> lymphatic trunks -> lymphatic ducts (can be seen w naked eye)

lymph nodes along collecting lymphatic vessels, remove pathogens from lymph

Lymph enters the node via afferent vessels and exits via efferent vessels. There are more afferent vessels, so lymph becomes “stuck” in nodes and stays longer for processing.

Question 22

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Describe the concepts of preload and afterload.

Answer 22

preload stretch of cardiomyocytes before contraction
impacted by => venous return and EDV
high preload (fluid overload or heart failure) = high SV is Frank-Starling Law
(heart fills with more blood if more stretched out)

afterload resistance the heart must overcome to eject blood
impacted by => arterial pressure and vascular resistance
high afterload (Systemic Vascular Resistance SVR, valve conditions ie. aortic stenosis) = high workload of heart (must use more pressure to eject blood)
if chronic high afterload, => hypertrophy

Question 23

Describe the parts of an EKG.

Answer 23

EKG can describe the 4 steps of heart contraction.
P-wave atrial depolarization
QRS complex ventricular depolarization (atrial REpolarization is masked)
T-wave ventricular repolarization

Question 24

Describe the pacemaker properties displayed by the heart.

Answer 24

sinoatrial node = the boss
1. SA sets the heart rate by overriding pacemaker rates of other heart structures
2. Atrioventricular node slows conduction to allow atrial contraction to complete, increase filling of ventricles, prevent simeltaneous atrial/ventricle contraction and protect ventricle from high HRs.

Pacemaker potential of nodal cells
1. slow depolarization (pacemaker potential) (increase in Na, AKA funny current)
2. self-induced action potential(Ca2+ in, then K+ out)

Question 25

Describe the phases of cardiac ventricular action potentials.

Answer 25

Phase 0 rapid depolarization (Na+ incr.)
Phase 1 inital repolarization (K+ decr.)
Phase 2 plateau (Ca2+ incr. = K+ decr.)
Phase 3 rapid depolarization (K+ decr.)
Phase 4 Resting Membrane Potential

Question 26

Describe the phases of the cardiac cycle.

Answer 26

mid-diastole passive filling (valves open and ventricles relaxed)
atrial systole atrial depolarization (blood pushed into ventricles)
isovolumetric ventricular contraction ventricular depolarization (valves close, ventricular pressure incr.)
ventricular ejection systole
VP>AP => semilunar valve open
most blood ejected
VP<AP => valve closes
=> blood falls back into heart
isovolumetric relaxation diastole/Quiescent period filling

Question 27

Define stroke volume, EDV, ESV, CO, EF and their equations.

Answer 27

Stroke Volume (SV) blood ejected from L. ventricle per 1 heart beat.
End-Systolic Volume (ESV) blood in L.ventricle when heart is mostly empty
End-Diastolic Volume (EDV) blood in L.ventricle when heart is full
Cardiac Output (CO) [L/min] rate of blood ejection

SV=EDV - ESV
CO=SV x HR

Ejection Fraction (EF%) measure performance
EF%= (SV/EDV) x 100