Thorax 1.3

Question 1

What is the mammary gland? Where is it?

Answer 1

a modified sweat gland located in the superficial fascia

Question 2

What are the lobes of granular tissue separated by?

Answer 2

fibrous septa

Question 3

What does each lobe open to?

Answer 3

a lactiferous duct that dilates just beneath the nipple to form a lactiferous sinus, or reservoir, for milk during lactation

Question 4

What are the suspensory ligaments in mammary gland?

Answer 4

strong fibrous connective tissue strands that pass from the dermis of the skin to the superficial fascia through the substance of the breast

Question 5

Where does the lymphatic drainage in the breast go to?

Answer 5

1. About 75% of the lymphatic drainage of the breast passes to the axillary lymph nodes
2. Lymph also may drain to infraclavicular nodes, medially to parasternal nodes, or inferiorly to abdominal lymphatics

Question 6

What is the beret divide into?

Answer 6

quadrants:
- upper inner
- upper outer
- lower inner
- lower outer

Question 7

Where do breast cancer usually develop?

Answer 7

• Approximately 50% of all breast cancers develop in the upper outer quadrant.
• Breast cancer is the most common malignancy in women.
• Its incidence exceeds the combined incidences of the next 2 most common cancers, which are of the lung and colorectal area.
• Most of these neoplasms are ductal carcinomas

Question 8

Where do the lungs lie?

Answer 8

within pleural cavities composed of the parietal and visceral pleura

Question 9

Where is the parietal pleura?

Answer 9

lines the inner surface of the thoracic wall, superior aspect of the diaphragm, and mediastinum

Question 10

Where is the visceral pleura?

Answer 10

visceral pleura is intimately associated with the lung surface

Question 11

How is the visceral and parietal pleura related?

Answer 11

The visceral pleura reflects off the lung to become parietal pleura at the hilum of each lung, where structures enter and leave lung tissue

Question 12

What divides the lung?

Answer 12

• Oblique and horizontal fissures divide the right lung into:
  1. superior
  2. middle
  3. Inferior lobe
• An oblique fissure divides the left lung into a superior lobe and an inferior lobe

Question 13

What does the left lung contain?

Answer 13

The lingula roughly corresponds to the right lung’s middle lobe

Question 14

How many bronchopulmonary segments are in each lung?

Answer 14

Each lung contains 10 bronchopulmonary segments, each supplied by a segmental bronchus and an artery

Question 15

What is between the parietal and visceral pleura?

Answer 15

1. The potential space between the parietal pleura and visceral pleura contains only a small amount of serous fluid that lubricates the surfaces and reduces friction during respiration
2. If fluids (e.g., blood or edema) or air gain access to this potential space, it becomes a real space, and the pressure can partially compress the lung or collapse it completely.

Question 16

What is the hilum of each lung?

Answer 16

the point where the pulmonary vessels, bronchi, lymphatics, and nerves enter or leave the lung

Question 17

What happens at the hilum and along the pulmonary ligament?

Answer 17

the visceral pleura reflects from the lung surface to become the parietal pleura lining the mediastinum and inner aspect of the thoracic wall

Question 18

How do things lie viewed from the hilum?

Answer 18

Viewed from the hilum of each lung, the bronchi generally lie posteriorly, the pulmonary arteries superiorly, and the pulmonary veins anteriorly and inferiorly.

Question 19

What lobes do the right and left leg have?

Answer 19

• The right lung has superior, middle, and inferior lobes, demarcated by the horizontal and oblique fissures
• The left lung has a superior lobe and an inferior lobe

Question 20

What are the different types of lung cancer?

Answer 20

• Lung cancer is the leading cause of cancer-related deaths and is associated consistently with a 20- to 30-year history of smoking.
• Lung cancers are highly invasive and rapidly metastasizing tumors.
• Adenocarcinoma and squamous cell carcinoma are the most common types of lung cancer

Question 21

Where does the hear lie?

Answer 21

Within middle mediastinum

Question 22

What is the heart incase in?

Answer 22

within a fibroserous sac called the pericardium

Question 23

What is the outer layer of the pericardium?

Answer 23

The outer layer of the pericardium is the fibrous pericardium, a strong, fibrous layer that blends with the roots of the great vessels

Question 24

What is the serous pericardium?

Answer 24

Serous pericardium consists of an underlying parietal layer lining the inner aspect of the fibrous pericardium and a visceral layer that reflects onto the heart as the epicardium

Question 25

Where is the thymus?

Answer 25

• The thymus, often atrophied and imbued with fat in the adult, overlies the great vessels and superior portion of the pericardium
• It is usually directly posterior to the manubrium of the sternum

Question 26

When can cardiac tamponade occur?

Answer 26

• The pericardial cavity is a potential space between the 2 serous layers and contains a thin film of serous lubricating fluid to reduce friction of the beating heart
• Trauma to the heart or rupture of a vessel can lead to bleeding in the pericardial cavity, which compresses the heart and compromises its function. This condition is called cardiac tamponade

Question 27

What is pericarditis?

Answer 27

Pericarditis is an infection of the pericardium usually caused by a virus, although bacteria and fungi are also causative agents

Question 28

What is the pericardial cavity?

Answer 28

a potential space between the visceral serous pericardium (epicardium) and the parietal serous pericardium, which lines the inner surface of the fibrous pericardium

Question 29

What does the visceral serous do?

Answer 29

reflects off the heart around these large vessels and becomes the parietal serous pericardial layer.

Question 30

Where does the heart lie?

Answer 30

The heart (removed in this illustration) lies within the pericardial sac

Question 31

Where is the oblique pericardial sinus?

Answer 31

a cul-de-sac behind the left atrium of the heart, is another reflection of serous pericardium surrounding the pulmonary veins

Question 32

Where is pain sensation from the fibrous pericardium conveyed?

Answer 32

via the paired phrenic nerves (C3-C5), which course through this layer on their way to innervate the abdominal diaphragm

Question 33

What is the transverse sinus?

Answer 33

• The transverse sinus is a space between the reflections of the serous pericardium, which is posterior to the ascending aorta and pulmonary trunk, and anterior to the superior vena cava.
• This is a clinically important area because clamping these vessels can completely stop ventricular outflow

Question 34

What is the smooth portion of the right atrium?

Answer 34

• Sinus venarum
• because it develops from the embryonic sinus venosus and receives blood from the superior and inferior venae cavae and coronary sinus

Question 35

What is the sinus venarum separated from?

Answer 35

the more muscular portion of the atrium proper by a line, the crista terminalis

Question 36

What is the fossa ovalis?

Answer 36

the adult representation of the embryonic foramen ovale

Question 37

What are the walls like in the right and left atrium?

Answer 37

• right atrium is slightly larger than the left atrium
• right atrium has thinner walls because the pressure on the right side of the heart is normally lower than that on the left side.

Question 38

What is the auricle?

Answer 38

a pouch-like appendage of the atrium but is functionally identical to the rest of the atrium

Question 39

Are atrial septal defects common?

Answer 39

• Atrial septal defects make up 10% to 15% of congenital cardiac anomalies
• In such cases, blood flows from the higherpressure left atrium into the lower-pressure right atrium (left-toright shunt)

Question 40

What do the chord tendineae do?

Answer 40

connect papillary muscles to the cusps of the tricuspid, or right atrioventricular, valve

Question 41

What do the chord tendineae do in contraction of right ventricle?

Answer 41

prevent the valve cusps from everting into the right atrium

Question 42

What does the septomarginal trabecula (moderator band) of the trabeculae carneae do?

Answer 42

connects the interventricular septum to the base of the anterior papillary muscle

Question 43

What does this band of muscles do?

Answer 43

conveys a portion of the atrioventricular right bundle branch conduction system to the anterior papillary muscle

Question 44

What is the interventiruclar septum?

Answer 44

largely muscular, but its superior aspect contains a small membranous portion that is a common site for ventricular septal defects

Question 45

Are ventricular petal defect common? What do they result in?

Answer 45

1. Ventricular septal defect is the most common congenital heart defect
2. The most common site of occurrence is in the perimembranous region of the ventricular septum, just beneath the tricuspid and mitral valves
3. This defect results in a left-to-right shunt of blood and may precipitate congestive heart failure