Bisc 130 Thoracic Wall/contents Of The Thorax Ii

Front 1

What are the boundaries of the thoracic wall?

Back 1

Anterior: sternum and costal cartilages
Lateral: ribs and intercostal contents
Posterior: vertebral column and posterior portions of ribs

Front 2

What are the boundaries of the thoracic inlet and outlet?

Back 2

Inlet: 1st thoracic vertebrae, 1st rib, manubrium of the sternum
Outlet: 12th thoracic vertebra, lowest ribs, costal cartilages, xiphoid process of sternum

Front 3

What are the true ribs?

Back 3

Ribs 1-7, costal cartilages articulate directly with the sternum

Front 4

What are the false ribs?

Back 4

Ribs 8-12, costal cartilages of 8,9 and 10 articulate with cartilage of rib above; 11 and 12 have no anterior articulation and are called "floating ribs"

Front 5

What are the six parts of the typical rib?

Back 5

1. Head (w/ articular facets that articulate with vertebral column)
2. Neck
3. Tubercle (articular facet articulates with transverse process of vertebrae)
4. Shaft
5. Angle - point of maximum curvature
6. Costal groove (at inferior border)

Front 6

What is 'special' about the 1st rib?

Back 6

"Superlative" rib, broadest, strongest, flattest, most curved, usually shortest, with ONE facet on the head

Front 7

What is the 'uncertain rib'? Why is it called that?

Back 7

The 10th rib - it may articulate with the 9th cartilage or remain free as a floating rib

Front 8

What are the floating ribs? What do they have in common?

Back 8

The 11th and 12th ribs; they don't have any anterior articulation.
Both only have one facet on the head, and have no neck or tubercle
The 12th lacks an angle or costal groove.

Front 9

What innervates the intercostal muscles?

Back 9

The intercostal nerves

Front 10

How are neurovascular bundles arranged on the inferior borders of the ribs?

Back 10

(From superior to inferior)
VAN - Vein, Artery, Nerve

Front 11

What arteries supply the thoracic wall?

Back 11

Posterior intercostal and anterior intercostal arteries

Front 12

What artery supplies the upper two intercostal spaces?

Back 12

Posterior intercostal artery; branches from the highest intercostal artery, which is a branch of the costocervical trunk of the subclavian artery.

Front 13

What arteries supply the intercostals (below the first two)?

Back 13

Branches from the thoracic aorta and the anterior intercostal artery (from the internal thoracic branch of the subclavian artery)

Front 14

Where is the anterior intercostal artery located?

Back 14

It circles the thoracic cage in the intercostal spaces

Front 15

What veins drain the intercostal muscles?

Back 15

1. The azygos (drains right side intercostals) and hemiazygos (drains left side intercostals - may be absent - drains into azygos)
2. Anterior intercostal vein - drains into the internal thoracic vein (accompanies internal thoracic artery)

Front 16

What are the intercostal nerves?

Back 16

Ventral primary rami of thoracic spinal nerves (associated with blood vessels)

Front 17

Where does the subcostal nerve originate?

Back 17

From the 12th thoracic spinal nerves

Front 18

What is the region between the left and right pleural cavities in the thorax?

Back 18

The mediastinum

Front 19

Where are the plural cavities located and what fills them?

Back 19

There is a left and right plural cavity, and they are located between the visceral pleural lining and parietal pleural lining. The space is filled with serous fluid.

Front 20

What is a hemothorax? A pneumothorax?

Back 20

Both can be caused by blunt trauma to the chest.

In a hemothorax, blood enters the pleural cavity. In a pneumothorax, air enters the pleural cavity.

Front 21

What is the difference between visceral and parietal pleura?

Back 21

Visceral pleura dips into fissures and adheres to the lung. Parietal pleura lines the interior wall and is divided according to location.

Front 22

What are the four divisions of the parietal pleura?

Back 22

1. Mediastinal (next to the pericardium)
2. Costal (next to the costal cartilages)
3. Diaphragmatic (superior surface of the diaphragm)
4. Dome/cervical (apex of the lung)

Front 23

What are the functional compartments for gas exchange?

Back 23

Alveoli

Front 24

Primary bronchi divide into _______ and then to smaller _________.

Back 24

Bronchi; bronchioles

Front 25

What are the four sections of the lung?

Back 25

1. Apex - near the clavicle/cervical region (penetrating trauma above clavicle could puncture the apex)
2. Base (right above the diaphragm)
3. Right lung (3 lobes); left lung (2 lobes)
4. Root/hilus

Front 26

In the respiratory tract, what is the first place with no cartilage in the walls of the tube?

Back 26

Bronchioles

Front 27

What is the basic air pathway (four components)?

Back 27

Bronchus to bronchioles to alveolar ducts to alveolar sacs

Front 28

What are the six components of the hilus of the lung?

Back 28

1. Primary bronchus
2. Pulmonary artery
3. Pulmonary veins
4. Bronchial arteries and veins
5. Lymph vessels and nodes
6. Branches of vagus nerve and sympathetic trunk

Front 29

What do the pulmonary artery and veins do?

Back 29

The pulmonary artery is located above the bronchus and carries deoxygenated blood to the lungs.
The pulmonary veins are generally located below the bronchus and they carry oxygenated blood from the lungs to the heart.

Front 30

When foreign bodies are aspirated, which of the primary bronchi is most likely to be obstructed?

Back 30

The right bronchi, because it is more of a "straight shot" from the pharynx.

Front 31

What do the bronchial arteries (sup.) and veins (inf.) do?

Back 31

The bronchial arteries and veins bring oxygenated blood to and drain blood from lung tissue (respectively).

Front 32

Of the contents of the lung hilum, what is blackened by air pollutants (not necessarily smoking)?

Back 32

Lymph nodes

Front 33

What are the boundaries of the imaginary plane between the superior and anterior/middle/posterior sections of the mediastinum?

Back 33

The plane is between the sternal angle and the disc between the 4th and 5th thoracic vertebrae.

Front 34

What are the four divisions of the mediastinum?

Back 34

1. Superior (toward the thoracic inlet)
2. Anterior
3. Middle (surrounded by pericardium)
4. Posterior

Front 35

What region of the mediastinum contains the aortic arch, brachiocephalic veins, superior vena cava, vagus and phrenic nerves, esophagus, trachea, and thoracic duct?

Back 35

The superior mediastinum

Front 36

What are the three branches off the arch of the aorta (from right to left)?

Back 36

Brachiocephalic artery, left common carotid artery, and left subclavian artery

Front 37

What does the brachiocephalic artery branch into?

Back 37

The right common carotid and right subclavian arteries

Front 38

Where do the brachiocephalic veins drain into?

Back 38

The superior vena cava

Front 39

What is the vagus nerve? The phrenic nerve?

Back 39

1. Vagus - parasympathetic nerve to viscera of thorax (heart and lungs) and abdomen
2. Innervates the diaphragm

Front 40

What is the thoracic duct?

Back 40

A large lymphatic vessel that typically goes to the left brachiocephalic vein

Front 41

What makes up the anterior mediastinum?

Back 41

Loose (areolar) connective tissue

Front 42

What are the three components of the middle mediastinum?

Back 42

Pericardium, heart, and phrenic nerves

Front 43

What part of the medistinum includes the esophagus, descending aorta, vagus nerves, thoracic duct, and azygos and hemiazygous veins?

Back 43

The posterior mediastinum

Front 44

What do the azygous and hemiazygous veins do?

Back 44

The azygous is located more to the right, draining the right intercostal muscles.
The hemiazygous may be absent, but if present, it is more to the left, draining the left intercostals, then emptying into the azygous.

Front 45

How big (approximately) is a normal heart?

Back 45

The size of a fist

Front 46

Describe the heart in anatomical position.

Back 46

The apex points down and to the left and the base points opposite.
The right heart is anterior, and the left heart is posterior.

Front 47

What are the two layers of the pericardium?

Back 47

The outer fibrous layer and inner serous layer (serous fluid deep to tissue - keeps the heart surrounded by fluid, keeping mechanical functions running smoothly)

Front 48

How is mechanical activity divided in the heart?

Back 48

Superiorly and inferiorly

Front 49

True or false: The ventricles of the heart contract simultaneously.

Back 49

True

Front 50

What is the flow of blood through the heart (beginning in the sup/inf. vena cava)?

Back 50

Right atrium --> right ventricle --> pulmonary trunk --> pulmonary arteries --> lungs --> pulmonary veins --> left atrium --> left ventricle --> aorta

Front 51

True or false: The right ventricle has a thicker, more muscular wall than the left ventricle.

Back 51

False

Front 52

What are the five great vessels coming to/from the heart?

Back 52

Superior vena cava, inferior vena cava, pulmonary veins (4), pulmonary artery, and the aorta

Front 53

Which side of the heart has a higher oxygen content?

Back 53

The left side of the heart

Front 54

What valves are closed during ventricular systole?

Back 54

Tricuspid (right) and bicuspid (left) valves (atrioventricular valves)

Front 55

What valves are closed during ventricular diastole?

Back 55

Pulmonary semilunar and aortic semilunar

Front 56

Where are the bicuspid and tricuspid valves located?

Back 56

Bicuspid (mitral)- between the left atrium and ventricle
Tricuspid - between the right atrium and ventricle

Front 57

Where is the fossa ovalis located? What embryonic opening does it form from?

Back 57

Located in the atrial septum; depression formed from the foramen ovale

Front 58

What are the two parts of the ventricular septum? Which part is more likely to have a ventricular septum defect?

Back 58

1. Muscular (inf.)
2. Membranous (sup.) - can have a ventricular septum defect if not fully formed

Front 59

What is a ventricular septum defect?

Back 59

The most common cardiac defect; the ventricular septum doesn't fully form, causing recirculation of oxygenated blood through the lungs = less blood to the periphery.
Often results in breathing problems during activity.

Front 60

What are the trabeculae carnae?

Back 60

Irregularities in the inner surface of both ventricles.

Front 61

What are the papillary muscles? What do they do?

Back 61

Fingerlike muscles in both ventricles that are attached to the AV valves by chordae tendineae.
These muscles keep the AV valves closed during contraction (systole). They do NOT open the valves.

Front 62

Where are the pectinate muscles located?

Back 62

In the right inner atrial wall.

Front 63

Where is the SA node located? The AV node?

Back 63

SA node: wall of right atrium
AV node: floor of right atrium

Front 64

What is order of the conduction system of the heart?

Back 64

Electrical pulse starts in the SA node, goes to the AV node, to the Bundle of His (splitting into left and right bundle branches), and to the Purkinje fibers

Front 65

What is the pacemaker of the heart?

Back 65

SA node

Front 66

What innervates the conduction system of the heart (esp. SA node)?

Back 66

The vagus (parasympathetic) and sympathetic nerves

Front 67

What do parasympathetic and sympathetic innervation do to heart rate?

Back 67

Parasympathetic: decreases heart rate
Sympathetic: increases heart rate

Front 68

Where are the following conduction components located in the heart:
-Bundle of His
-Left and right bundle fibers
-Purkinje fibers

Back 68

1. Bundle of His: in the membraneous ventricular septum
2. Left and right bundle fibers: go through muscular septum to walls of ventricles
3. Purkinje fibers: between ventricular muscle cells

Front 69

What two cardiac vessels branch from the left coronary artery? What do they supply?

Back 69

1. Circumflex artery: supplies left atrium and ventricle
2. Anterior descending: interventricular; between ventricles - supplies both

Front 70

What two cardiac vessels branch from the right coronary artery? What do they supply?

Back 70

**smaller vessels off the right coronary artery supply the right atrium**

1. Marginal artery: down the right margin of the heart; supplies the right ventricle
2. Posterior descending artery: between ventricles; supplies both

Front 71

What are the cardiac veins?

Back 71

1. Great cardiac vein (anterior)
2. Middle cardiac vein (posterior)
**both are next to interventricular arteries**

Front 72

Where do the cardiac veins drain to?

Back 72

They drain into the coronary sinus (between the left atrium and ventricle), then the sinus empties blood into the right atrium.

Front 73

What do the following embryonic circulatory structures become after birth?
1. Umbilical artery
2. Umbilical vein
3. Ductus venosus
4. Ductus arteriosus

Back 73

1. Umbilical artery --> medial umbilical ligament
2. Umbilical vein --> ligamentum teres hepatis
3. Ductus venosus --> ligamentum venosum
4. Ductus arteriosus --> ligamentum arteriosum

Front 74

Describe embryonic circulation.

Back 74

-Fetal blood is oxygenated at the placenta, and the oxygenated blood re-enters the umbilical vein.
-The umbilical vein is shunted through the liver through the ductus venosus into the inferior vena cava.
-Oxygenated blood is pressurized and tends to pass from the right atrium to the left atrium via the foramen ovale. This is technically a lung bypass - fetal lungs are non-functioning.
-Some blood does go to the lungs, but blood from the pulmonary trunk goes through the ductus arteriosus to the aorta.

Front 75

Describe the transformation from fetal to infant circulation (after birth).

Back 75

-Smooth muscle in the umbilical arteries constrict (becomes the ligamentum teres), and blood is drained through the umbilical vein to the ductus venosus.
-As the the structures drain, they close and become ligaments.
-The ductus arteriosus constricts and becomes the ligamentum arteriosus (between the pulmonary arteries and the aorta) = lung bypass closes, so blood begins to fill the lungs.
-More blood in the left atrium, and the pressure from the increased volume closes the foramen ovale.

Front 76

What happens if the foramen ovale doesn't close completely?

Back 76

Can have right to left shunting of blood. This results in poor oxygenation (cyanotic) and usually requires surgery to repair.

Front 77

What coronary vessel is most often blocked?

Back 77

The anterior descending artery ("Artery of Death")

Front 78

What happens in coronary artery disease?

Back 78

Coronary arteries become blocked (ex: with plaque - atherosclerosis). As a result, the heart becomes ischemic = myocardial infarction.