ANAPHY MT 100 LEC - Respiratory System

Oxygen (O2); Carbon Dioxide (CO2)

The respiratory system supplies _____ and removes _____.

Cardiovascular system

What other system does the respiratory system work in conjunction with?

acid-base balance and voice production

Enumerate what the respiratory system contributes to

pulmonary ventilation;

external respiration;

transport of respiratory gases;

internal respiration

enumerate the four processes of the respiratory system

Conducting and Respiratory Zone

Enumerate the divisions of the respiratory system

Conducting Zone

Conducts air into the lungs, filters dust and microorganisms, warms inspired air, humidifies inspired air

Conducting Zone

No gas exchange occurs in this region

Nose → Nasal cavity → Pharynx → Larynx → Trachea → Primary bronchi → Secondary bronchi → Tertiary bronchi → Bronchioles → Terminal bronchioles

enumerate the flow of the conducting zone

Respiratory Zone

Primary site of gas exchange (external respiration)

Respiratory bronchioles → Alveolar ducts → Alveolar sacs → Alveoli

enumerate the flow of the respiratory zone

Nose

forms the entrance to the respiratory tract

nasal septum

The nose is divided into right and left nasal cavities by the _____

external nares (nostrils)

The anterior opening of the nose

Internal nares (Choanae)

The posterior opening of the nose

Internal nares (Choanae)

This leads to the nasopharynx

Superior turbinate;

Middle turbinate;

Inferior turbinate

Enumerate the Nasal Conchae (Turbinates)

Nasal conchae (turbinates)

Curved body projections that increase surface area, create air turbulence, and improve warming and humidification

Paranasal Sinuses

Air-filled cavities found within the skull bone

frontal sinus, maxillary sinus, ethmoid sinus, sphenoid sinus

Enumerate the types of Paranasal Sinuses

Paranasal Sinuses

This lightens the skull, produces mucus, warms and humidifies inspired air, and enhances voice resonance

Pharynx

A muscular tube extending from the posterior nasal cavity to the esophagus

Food and Air

The pharynx is a passageway for

Nasopharynx;

Oropharynx;

Laryngopharynx

Enumerate the 3 parts of the pharynx

Nasopharynx

located posterior to the nasal cavity

Pharyngeal tonsils (adenoids)

Enumerate the tonsils in the Nasopharynx

Nasopharynx

conducts air only, contains the pharyngeal tonsil (adenoids), opens in to the pharyngotympanic tubes

Oropharynx

located posterior to the oral cavity

Palatine and Lingual tonsils

Enumerate the tonsils in the oropharynx

Oropharynx

conducts food and air, contains palatine tonsils and lingual tonsils

Laryngopharynx

most inferior region of the pharynx

N/A

Enumerate the tonsils in the Laryngopharynx

Laryngopharynx

common passageway for food and air, connects to the esophagus and larynx

Larynx (Voice Box)

cartilaginous organ connecting the pharynx to the trachea

Larynx (Voice Box)

Maintains an open airway, Produces sound (phonation), Prevents aspiration during swallowing

Thyroid Cartilage, Cricoid Cartilage, Arytenoid Cartilage, Epiglottis

Enumerate the major cartilages in the Larynx

Thyroid Cartilage

Largest laryngeal cartilage, forming the adams apple

Cricoid Cartilage

Only complete ring of cartilage that surrounds the airway,

Inferior to the thyroid cartilage

Arytenoid Cartilage

Anchors the vocal folds to control tension during speece

Elastic Cartilage

The epiglottis is what type of cartilage?

Laryngeal Inlet

The epiglottis covers the ____ when swallowing

Epiglottis

Prevents food and liquids from entering the trachea

True and False vocal folds/cords

Enumerate the types of vocal folds

True Vocal Folds

Produces sound through vibration

False Vocal Folds

Provides protection and does not produce sound

Trachea

flexible airway that extends from the larynx to the primary bronchi

Trachea

Approximately 10-12 cm long and 2.5 cm in diameter

Cricoid Cartilage; Carina

The trachea begins inferior ton the ____, and ends at the _______. where it divides into the right and left primary bronchi

Trachea

Lies anterior to the esophagus

Trachea

Supported by 16-20 C-shaped hyaline cartilage rings that prevent airway collapse

16-20 C Shaped hyaline cartilage rings

The trachea is supported by

Bronchial

The trachea branches repeatedly to distribute air throughout the lungs

Lungs

are paired, cone- shaped organs occupying most of the thoracic cavity

Situated on either side of

the mediastinum;

Extend from just above the

clavicle to the diaphragm

State the location of the lungs

Apex, Base, Costal Surface, Mediastinal Surface

Enumerate the external features of the lungs

Apex

Superior pointed portion that extends 2-3cm above the clavice

Base

Broad inferior portion resting on the diaphragm

Costal Surface

Convex surface facing the ribs

Mediastinal Surface

Faces the heart and mediastinum, containing the hilum

Hilum

The medial "gateway" of each lung where structures enter and leave

Primary bronchus;

Pulmonary artery;

Pulmonary veins;

Bronchial vessels;

Lymphatic vessels;

Pulmonary nerves

Enumerate the structures in the root of the lung

Alveoli

are microscopic air sacs where external respiration occurs

Type 1 Alveolar cells, Type 2 Alveolar cells, Alveolar Macrophages, Alveolar Pores

Enumerate the Alveolar Cells

Type I Alveolar Cells

Form the thin respiratory membrane for rapid gas diffusion, Cover approximately 95% of the alveolar surface

Type II Alveolar Cells

Secretes pulmonary surfactant

pulmonary surfactant

reduce alveolar surface tension, prevent alveolar collapse during respiration

Alveolar Macrophages (Dust Cells)

Phagocytic cells in the lungs

Alveolar Pores (Pores of Kohn)

Small openings connecting adjacent alveoli; equalizes air pressure

Respiratory (Alveolar- Capillary) Membrane

thin barrier across which oxygen and carbon dioxide diffuse

Thin film of alveolar fluid containing surfactant;

Type I alveolar epithelium;

Fused basement membrane;

Capillary endothelium

Enumerate the layers of the Respiratory (Alveolar- Capillary) Membrane

Extremely thin (approximately 0.5 μm);

Large surface area (~70 m2);

Rich capillary network;

Allows rapid diffusion of respiratory gases

Enumerate the characteristics of the Respiratory (Alveolar- Capillary) Membrane

Thin membrane;

Large surface area;

Adequate blood flow;

Partial pressure gradients of O2 and CO2

Enumerate the factors affecting gas exchange

Pleura

a double-layered serous membrane surrounding each lung

Visceral Pleura and Parietal Pleura

Enumerate the two layers of the Pleura

Visceral Pleura

Firmly adheres to the lung surface, Covers the lobes and fissures

Parietal Pleura

Lines the thoracic wall, diaphragm, mediastinum

thoracic wall, diaphragm, mediastinum

The parietal pleura lines the

pleural cavity

a potential space between the pleural layers containing a small amount of pleural fluid

Reduces friction during breathing;

Allows smooth movement of the lungs;

Maintains negative intrapleural pressure

Enumerate the functions of the pleura fluid

negative intrapleural pressure,

This helps keep the lungs expanded

Pneumothorax

occurs when there is no negative intrapleural pressure, thus affecting the lungs partially or completely

Pulmonary Ventilation (Breathing)

the movement of air into and out of the lungs

Pulmonary Ventilation (Breathing)

air moves from areas of higher pressure to lower pressure

pressure is inversely proportional to volume

State Boyles Law

increases; decreases

As thoracic volume ________, intrapulmonary pressure __________

Inspiration

an active process

Diaphragm, external intercostal muscles

Enumerate the muscles involved in inspiration

Diaphragm contracts and flattens;

Rib cage moves upward and outward;

Thoracic cavity volume increases;

Intrapulmonary pressure falls below atmospheric pressure;

Air enters the lungs

Enumerate the events that occur during inspiration

Expiration

a usually passive process

Diaphragm relaxes;

External intercostals relax;

Elastic recoil of the lungs decreases thoracic volume;

Intrapulmonary pressure rises above atmospheric pressure;

Air flows out

Enumerate the events that occur during expiration

internal intercostals, abdominal muscles

Forced expiration requires contraction of

Exercise, coughing, sneezing, and blowing

Forced expiration occurs during:

Atmospheric pressure;

Intrapulmonary pressure;

intrapleural pressure

Enumerate the pressure changes during breathing

Atmospheric pressure

pressure exerted by air surrounding the body

Intrapulmonary pressure

pressure within the alveoli that falls during inspiration, rises during expiration

Falls during inspiration, rises during expiration

Intrapulmonary pressure falls and rises when?

Intrapleural pressure

pressure within the pleural cavity

Intrapleural pressure:

normally remains negative relative to atmospheric pressure, helps prevent lung collapse

Lung Compliance

The ease with which the lungs expand during inspiration

High Compliance

lungs expand easily

Low Compliance

greater effort is needed to inflate the lungs