7 - Thoracic Cavity

Question 1

Pulmonary Arteries

Answer 1

Send deoxygenated, mixed venous blood to the lungs

Question 2

Pulmonary Veins

Answer 2

Return oxygenated blood from the lungs to the left atrium

Question 3

Aorta

Answer 3

Carries oxygenated blood from the left ventricle to the systematic circulation

Question 4

Superior and inferior vena cava

Answer 4

returns blood from upper and lower body to the heart, drains into the right atrium

Question 5

Expansion of the ribcage during respiration directions

Answer 5

anteroposterior
lateral
vertical (due to contraction of the diaphragm)

Question 6

Diaphragm

Answer 6

• seals the thoracic outlet
• Innervation through the phrenic
  nerve (C3,4,5)

Question 7

How do you think the intercostal muscles will participate in breathing mechanics?

Answer 7

intercostal muscles are engaged in respiratory stress

expand and contract the ribs to allow space for the lungs in the anteroposterior, lateral, and vertical directions

Question 8

How does the link between pulmonary circulation and body circulation work?

Answer 8

Pulmonary circulation moves blood between the heart and the lungs. The oxygenated blood then flows back to the heart. Systemic/body circulation moves blood between the heart and the rest of the body. It sends oxygenated blood out to cells and returns deoxygenated blood to the heart.

Question 9

how does fluid surrounding the pleura aid respiration?

Answer 9

• if there’s fluid between, you have a surface tension when you expand the thorax and you hare able to expand the lungs and pull them wider
• less friction

Question 10

bronchii

Answer 10

Covered in cartilage so they don’t collapse under the pressure of inhalation

Question 11

why is there no cartilage within the lungs?

Answer 11

The surface area increases further into the lungs which will increase the surface tension since there is fluid around Bronchiole and Alveoli

Question 12

Parts of the airway

Answer 12

Nose 
Mouth 
Pharynx 
Larynx 
Trachea 
Bronchi 
Lungs 
Lobes 
Lobule 
Bronchiole
Alveoli

Question 13

Parts of the airway

Answer 13

Nose 
Mouth 
Pharynx 
Larynx 
Trachea 
Bronchi 
Lungs 
Lobes 
Lobule 
Bronchiole
Alveoli

Question 14

What is the consequence of pulmonary hypertension on the heart?

Answer 14

High pressure strains the right ventricle of the heart, causing it to expand in size. Overworked and enlarged, the right ventricle gradually becomes weaker and loses its ability to pump enough blood to the lungs. This could lead to the development of right heart failure.

Question 15

What would the result of tricuspid valve damage be for the hemodynamics of the right heart?

Answer 15

It leads to backward flow of blood into the right atrium during systole; when the tricuspid regurgitation is only mild or moderate, this has no major hemodynamic consequences because the right atrium is very compliant.

Question 16

The tricuspid valve is susceptible to bacterial damage - why? How do the bacteria get to the tricuspid valve?

Answer 16

The heart valves are not supplied directly with blood. Therefore, the body’s immune response system, such as the infection-fighting white blood cells, cannot directly reach the valves through the bloodstream. Bacteria introduced into the blood stream flowing through the valve can lodge on heart valves and cause infection of the endocardium. If bacteria begins to grow on the valves, it is difficult to fight the infection

Question 17

Why is the thickness of the left ventricle greater than that of the right ventricle?

Answer 17

left ventricle needs to generate more pressure, systolic pressure, so it has more muscle (papillary muscles)

Question 18

Papillary muscles

Answer 18

Attach to valves via chore tendinae and prevent prolapse of valve cusps

Question 19

What is the consequence of mitral valve stenosis?

Answer 19

Mitral valve stenosis can strain your heart and decrease blood flow. Untreated, mitral valve stenosis can lead to complications such as Pulmonary hypertension

Question 20

What is the function of the chordae tendinae?

Answer 20

The chordae tendineae are a group of tough, tendinous strands in the heart. They are commonly referred to as the “heart strings” since they resemble small pieces of string. They play a vital role in holding the atrioventricular valves in place while the heart is pumping blood.

Question 21

Important features of the Right Ventricle

Answer 21

tricuspid valve
papillary muscles
chordae tendinae
moderator band 
pulmonary valve

Question 22

Important features of the Right Atrium

Answer 22

openings of the superior and inferior vena cava
opening of the coronary sinus
opening of the tricuspid valve
fossa ovalis

Question 23

Important features of the Left Ventricle

Answer 23

two cusps of the mitral valve
papillary muscles
chordae tendinae
cusps of the aortic valve
interventricular septum

Question 24

Important features of the Left Atrium

Answer 24

opening of the pulmonary veins

opening of the mitral valve