Lecture 42- Respiratory System Part 2

Question 1

What is Respiratory Distress Syndrome characterized by?

Answer 1

Difficulty breathing due to collapse of the alveoli

Question 2

What do premature babies not have a significant amount of in their lungs?

Answer 2

Surfactant

Question 3

What are the three layers in the blood-air barrier that gas exchange happens across?

Answer 3

1. Alveolar cell layer
2. Capillary Endothelial layer
3. Fused basement membrane

Question 4

How many lobes does the right lung have?
What are they called?
What are they separated b?

Answer 4

-Three lobes
-Superior, middle, and inferior
-Separated by an oblique fissure AND horizontal fissure

Question 5

How many lobes does the left lung have?
What are they called?
What are they separated b?

Answer 5

-Two lobes
-Superior and inferior
-Separated by an oblique fissure ONLY

Question 6

What is a pulmonary lobectomy?

Answer 6

Surgical removal of a cancerous/diseased segment of the lung, rather than the entire organ

Prevents spreading to other parts of organ

Question 7

What covers the inner surface of the thoracic wall and extends over the diaphragm?

Outer layer

Answer 7

Parietal Pleura

Question 8

What covers the outer surface of the lungs, extending into the fissures between the lobes?

Inner layer

Answer 8

Visceral Pleura

Question 9

What are the two functions of Pleural fluid?

Answer 9

1. Lubricates the pleural cavity (less friction)
2. Creates a fluid bond which connects thoracic cavity and lungs to change in volume together

Question 10

External respiration the exchange of oxygen between the body’s ______ ____ and the ____ ______

Answer 10

Interstitial fluids- fluid surrounding cells

External environments- space inside alveoli where air from the outside world enters in

Question 11

What type of respiration is the absorption of oxygen and the release of carbon dioxide by cells called?

Answer 11

Internal Respiration

Question 12

What is pulmonary ventilation?

Answer 12

Essentially breathing- physically moving air into and out of the lungs

Question 13

What are the two locations that gas exchange occurs across the blood-air barrier?

Answer 13

1. Lungs
2. Tissues

Question 14

Where does the transport of oxygen and carbon dioxide occur? (2)

Answer 14

1. Between alveolar capillaries
2. Between capillary beds in other tissues

Question 15

What causes pulmonary ventilation?

Answer 15

Changes in thoracic cavity volume, which lead to pressure differences

Question 16

Boyle’s Law states that when volume decreases, collision frequency and pressure will (decrease/increase/stay the same)

Answer 16

Increase

Question 17

Boyle’s Law states that when volume increases, collision frequency and pressure will (decrease/increase/stay the same)

Answer 17

Decrease

Question 18

What are the four factors that favor an increase in lung volume (inspiration)?

Answer 18

1. Muscle contraction- lowers the floor of thoracic cavity/expands rib cage
2. Negative intrapleural pressure- helps suction the lungs to thoracic wall
3. Elastic recoil of the thoracic wall
4. Surfactant in alveoli

Question 19

What is the pressure from least to greatest when breathing in between the atmosphere, lungs, and intrapleural space?

Answer 19

PIP<PA<Patm

OR

Intrapleural space<Lungs/Alveoli<Atmosphere

Question 20

What is the pressure from least to greatest when breathing out between the atmosphere, lungs, and intrapleural space?

Answer 20

PIP < PA > Patm

OR

Intrapleural space< Lungs/Alveoli> Atmosphere

Question 21

If the pleural sac is punctured, what happens to the intrapleural pressure/volume? What will the lung do as a result?

Answer 21

Intrapleural pressure equalizes with atmospheric pressure.

Intrapleural volume increases

Lung collapses

Question 22

What does compliance mean?

Answer 22

A measure of how easy it is to inflate the lungs

Question 23

What does compliance of the lungs and alveoli depend on? (2)

Answer 23

1. Negative intrapleural pressure
2. Surfactant- disrupts hydrogen bonds in water layer to decrease surface tension

Question 24

Would a smaller or larger alveoli will require a greater concentration of surfactant to maintain compliance?

Answer 24

Smaller

Smaller alveoli=greater pressure=needs more surfactant

Question 25

What two factors favor a decrease in lung volume (expiration)?

Answer 25

1. Elastic recoil of alveolar walls
2. Muscle contraction for forced expiration/pushes abdominal contents up against the thoracic cavity