Respiratory System Physiology Flashcards Preview

BIO 233 > Respiratory System Physiology > Flashcards

Flashcards in Respiratory System Physiology Deck (24):
1

Tidal Volume (TV)

Amount of air inhaled or exhaled with each breath under resting conditions

500 mL

2

Inspiratory Reserve Volume (IRV)

Amount of air that can be forcefully inhaled after a normal tidal volume inhalation

3100 mL

3

Expiratory Reserve Volume (ERV)

Amount of air that can be forcefully exhaled after a normal tidal volume exhalation

1200 mL

4

Residual Volume (RV)

Amount of air remaining in the lungs after a forced exhalation

1200 mL

5

What are the respiratory volumes?

  1. Tidal volume (TV)
    1. 500 mL
  2. Inspiratory reserve volume (IRV)
    1. 3100 mL
  3. Expiratory reserve volume (ERV)
    1. 1200 mL
  4. Residual volume (RV) 
    1. 1200 mL

6

Total lung capacity (TLC)

Maximum amount of air contained in the lungs afters a maxium inspiratory effort

TLC = TV + IRV + ERV + RV

~6000 mL

7

Vital capacity (VC)

Maximum amount of air that can be expired after a maximum inspiratory effort

VC = TV + IRS + RV

(Should be 80% of TLC)

~4800 mL

8

Inspiratory capacity (IC)

Maximum amount of air that can be inspired after a normal expiration

IC = TV + RV

~3600 mL

9

Functional residual capacity (FRC)

Volume of air remaining in the lungs after a normal tidal volume expiration 

FRC = ERV + RV

~2400 mL 

10

What are the respiratory capacities?

  1. Tidal lung capacity (TLC)
    1. TLC = TV+IRV+ERV+RV
    2. ~6000 mL
  2. Vital capacity (VC)
    1. VC = TV+IRV+ERV
    2. ~4800 mL
  3. Inspiratory capacity (IC)
    1. IC = TV + IRV
    2. ~3600 mL
  4. Functional residual capacity (FRC)
    1. FRC=ERV+RV
    2. ~2400 mL 

11

What keeps the lungs inflated? 

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Negative Pressure 

12

What are the two primary muscles of inspiration? 

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  1. Diaphragm
  2. External intercostals 

13

What is the sequence of events for inspiration?

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Inspiration

  1. Inspiratory muscles contract (diaphragm descents; rib cage rises)
  2. Thoracic cavity volume increases
  3. Lungs stretched; intrapulmonary volume increases
  4. Intrapulmonary pressure drops (to -1 mm Hg)
  5. Air (gases) flows into lungs down its pressure gradient until intrapulmonary pressure is equal to 0 
    1. Equal to atmospheric pressure 

14

During inspiration what happens to the inspiratory muscles?

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Inspiratory muscles contract

  • Diaphragm descends
  • Ribs elevate and sternum flares as external intercostals contract 

15

During inspiration what happens to the volume in the thoracic cavity? 

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Thoracic cavity volume increases during inspiraton 

16

What happens to the lungs during inspiration? 

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Lungs are stretched during inspiraton 

17

What happens to intrapulmonary volume during inspiration? 

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Intrapulmonary volume increases during inspiration 

18

What happens to intrapulmonary pressure during inspiration? 

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Intrapulmonary pressure decreases during inspiration

  • Pressure drops from 0 mm Hg to -1 mm Hg

19

During inspiration where do the gases (air) travel to and how? 

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Air (gases) travel into lungs down its pressure gradient

20

How much air (gases) is in the lungs during inspiration is needed before beginning expiration? 

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Until the intrapulmonary pressure is 0 

Equal to atmospheric pressure 

21

What are the two primary muscles used for expiration? 

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Muscles used in expiration

  1. Internal intercostals 
  2. Rectus abdominus 

22

What is the sequence of events for expiration? 

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  1. Inspiratory muscles relax
    1. Diaphragm rises
    2. Rib cage descends due to gravity
  2. Thoracic cavity volume decreases
  3. Elastic lungs recoil passively
    1. Intrapulmonary volume decreases
  4. Intrapulmonary pressure rises (to +1 mm Hg)
  5. Air (gases) flows out of lungs down its pressure gradient until intrapulmonary pressure is 0

23

What happens to the inspiratory muscles during expiration? 

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Inspiratory muscles relax during expiration 

  1. Diaphragm rises
    1. Diaphragm moves superiorly as it relaxes
  2. Ribcage descends due to gravity 
    1. Ribs and sternum depressed as external intercostals relax 

24

What happens to the thoracic cavity volume during expiration?

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