Ultimate Respiratory and Digestive Review Guide

Functions of the Respiratory System

• air movement, gas exchange

• regulates pH

• voice production

• olfaction

• protection against pathogens, dehydration, and temperature changes

This enzyme is present on the lungs cellular surfaces

angiotensin converting enzyme (ACE)

Pulmonary ventilation / Ventilation

movement of air into and out of the lungs

Perfusion

exchanging of gases

External respiration

movement of oxygen from lungs → blood, movement of CO2 from blood → lungs

Internal respiration

movement of oxygen from blood → cell interior, movement of CO2 from cell interior → blood

Cellular respiration

• breakdown of glucose, fatty acids, and amino acids

• results in the creation of ATP

Cellular respiration location

mitochondria of cells

Zones of the respiratory system

• conducting zone

• respiratory zone

Function of conducting zone

• move air (aka ventilation)

• filters, humidifies, warms air

What type of epithelium is found in the conducting zone

pseudostratified ciliated columnar epithelium

Structures in the conducting zone

• nasal cavity

• nasopharynx, oropharynx, laryngopharynx

• larynx

• trachea

• bronchi

• terminal bronchioles / nares

Function of respiratory zone

respiratory zone does gas exchange (perfusion) of O2 and CO2

What structure has the sites of gas exchange

alveoli

Type of epithelium found in the respiratory zone

simple squamous epithelium

Purpose of simple squamous epithelium in the respiratory zone

makes diffusion easier due to thin walls

Structures in the respiratory zone

• alveoli

• respiratory bronchioles

• alveolar ducts and sacs

Terminal bronchioles location

conducting zone of respiratory system

Respiratory bronchioles location

respiratory zone of respiratory system

3 sections of the pharynx

• nasopharynx

• oropharynx

• laryngopharynx

Epithelium found in nasopharynx

pseudostratified ciliated columnar epithelium

Epithelium found in oropharynx and laryngopharynx

stratified squamous non-keratinized epithelium

Functions of the Nasal Cavity

• air passageway

• clean, humidifies, warms air

• smell

• resonating chamber

Functions of the Larynx

• maintain open air passageway

• prevent swallowed material

• sound production

Sound production occurs in the

larynx

Types of alveolar cells

• Type I

• Type II

• Dust cells / alveolar macrophage

Function of Type I alveolar cells

Gas exchange

Composition of Type I alveolar cells on the alveolar surface

makes up 97% of surface

Type of epithelium found in Type I alveolar cells

simple squamous epithelium

Function of Type II alveolar cells

secrets surfactant

Function of surfactant

decreases surface tension

Type of epithelium found in Type II alveolar cells

simple cuboidal epithelium

Function of dust cells / alveolar macrophages

removes particles and other irritants in alveoli

Alveolar macrophages are derived from

monocytes

Layers of pleura

• parietal pleural

• pleural fluid

• visceral pleural

The outer layer of pleura is the

parietal pleural

The inner layer of pleura is the

visceral pleural

Boyle’s Law

states that pressure and volume of a gas have an inverse relationship

When the volume of a gas increases, the pressure of the gas will

decrease

When the volume of a gas decreases, the pressure of the gas will

increase

Dalton’s Law

the total pressure of gas is the sum of partial pressures of individual gases

Fick’s Law

states that distance is inversely proportional to the diffusion

Partial pressure of CO2 in pulmonary veins

40 mmHg

Partial pressure of O2 in the pulmonary veins

100 mmHg

Partial pressure of CO2 in pulmonary arteries

45 mmHg

Partial pressure of O2 in pulmonary arteries

40 mmHg

CO2 is __ times more diffusable than O2

10

An increase of surface and partial pressure difference will (increase/decrease) diffusion

increase

What is the most important factor for gas exchange

partial pressure difference

What is the primary muscle for respiration

diaphragm

Tidal volume

the amount of air inhaled and exhaled during a normal breathing cycle

What is the volume of tidal volume

500 mL

Inspiratory Reserve Volume

amount of air breathed in

Expiratory Reserve Volume

amount of air breathed out

Residual volume

amount of gas that stays in your lungs after you inhale and exhale

What is the volume of residual volume

1200 mL

Which of the following can’t be measured directly

residual volume

Importance of residual volume

• perfusion

• to prevent alveolar and lung collapse

Total lung capacity

total amount of exchangeable and nonexchangeable air

What is the volume range for total lung capacity

4200-6000 mL

Between breathes, intrapulmonary pressure is _________ atmospheric pressure

equal to

During inspiration, inspiratory muscles

contract

During inspiration, thoracic and lung volume

increase

During inspiration, the intrapulmonary pressure ______ to below atmospheric pressure

decreases

Between inspiration and expiration, intrapulmonary pressure ____ atmospheric pressure

equals

During expiration, inspiratory muscles

relax

During expiration, thoracic and lung volume

decreases

Intrapleural pressure will always be _____ than alveolar pressure

lower

Formula for total lung capacity

TLC = VC + RV

total lung capacity = vital capacity + residual volume

Normal respiratory rate (RR) is

12 breathes / min

Minute ventilation (Pulmonary ventilation, VM)

amount of air that moves into and out of lungs each minute

Formula for minute ventilation

VM = VT x RR

minute ventilation = tidal volume x respiratory rate

Vital capacity (VC)

maximal volume of gas that can be expired after a maximal inspiration

Formula for vital capacity

VC = IRV + TV + ERV

vital capacity = inspiratory reserve volume + tidal volume + expiratory reserve volume

What is the normal volume for vital capacity

4800 mL

Dead Space (VD)

volume of air not participating in gas exchange

Calculation for Dead Space

1 lb = 1 mL

Normal volume in a healthy adult for dead space is

150 mL

Warren weighs 212 pounds after eating McDonalds. What is his dead space?

212 mL

Alveolar Ventilation (VA)

volume available for gas exchange

Formula for Alveolar Ventilation

VA = (VT - VD) x RR

alveolar ventilation rate = (tidal volume - dead space) x respiratory rate

Normal range for Alveolar Ventilation

4200 mL

Force preventing Alveolar Collapse

Hydrogen bonds

What type of alveolar cells produce surfactant

Type II alveolar cells

Compliance

Measure of the ease of expansion

Higher compliance = ____ work

less

Lower compliance = ____ work

more

The partial pressure of oxygen in the alveolus is

100 mmHg

The partial pressure of oxygen in the pulmonary capillaries is

40 mmHg

The partial pressure of CO2 in the alveolus is

40 mmHg

The partial pressure of CO2 in the pulmonary capillaries is

45 mmHg

The partial pressure of oxygen in systemic capillaries is

100 mmHg

The partial pressure of oxygen in tissue cells is

40 mmHg

The partial pressure of CO2 in systemic capillaries is

40 mmHg

The partial pressure of CO2 in tissue cells is

45 mmHg

In regards to oxygen transport, __% of oxygen dissolve in plasma

1.5%

In regards to oxygen transport, __% of oxygen are bound to hemoglobin

98.5%

In regards to carbon dioxide transport, this percentage range is dissolved in plasma

7-10%

In regards to carbon dioxide transport, __% is bound to hemoglobin

20%

In regards to carbon dioxide transport, __% is transported as bicarbonate

70%