Environmental Exchange Fundamentals of Anatomy & Physiology Environmental Exchange

The Respiratory System

What are the primary functions of the respiratory system?

Oxygen Is obtained from the air by diffusion across delicate _______ surfaces of lungs Is carried to cells by the cardiovascular system which also returns _____ _____ to the lungs

5 Functions of the Respiratory System Provides extensive gas exchange _____ ____ between air and circulating blood Moves air to and from exchange surfaces of lungs

5 Functions of the Respiratory System ______ respiratory surfaces from outside environment ______ sounds-speaking, singing Participates in ________ sense

Components of the Respiratory System Figure 23–1

Organization of the Respiratory System The respiratory system is divided into the _______ respiratory system, above the larynx, and the _______ respiratory system, from the larynx down

The Respiratory Tract Consists of a ________ portion: from nasal cavity to terminal bronchioles Consists of a ___________ portion: the respiratory bronchioles and alveoli - Are air-filled pockets within the lungs where all gas exchange takes place

The Respiratory Epithelium For gases to exchange efficiently: alveoli walls must be very thin (< 1 µm) surface area must be very great (about __ times the surface area of the body)

The Respiratory Mucosa Consists of: an ________ layer an _______ layer Lines conducting portion of respiratory system

Alveolar sac Alveoli Figure 23–2

The Lamina Propria Underlies areolar tissue In the upper respiratory system, trachea, and bronchi: contains _______ glands that secrete onto epithelial surface In the conducting portion of lower respiratory system: contains _____ muscle cells that encircle lumen of bronchioles

The Respiratory Epithelium Figure 23–2

How are delicate respiratory exchange surfaces protected from pathogens, debris, and other hazards?

The Respiratory Defense System Consists of a series of _____ mechanisms Removes particles and _________

Components of the Respiratory Defense System (1 of 2) _______ cells and mucous glands: produce mucus that bathes exposed surfaces Cilia: _______ debris _______ in mucus toward the pharynx (mucus escalator)

Components of the Respiratory Defense System (2 of 2) _________ in nasal cavity removes large particles Alveolar _________ engulf small particles that reach lungs

What are the organs of the upper respiratory system and their functions?

The Upper Respiratory System Figure 23–3

The Nose Air enters the respiratory system: Nasal hairs: through nostrils or ______ nares into nasal _________ Nasal hairs: are in nasal vestibule are the first particle filtration system

The Nasal Cavity The nasal ________: divides nasal cavity into left and right Mucous secretions from paranasal sinus and tears: clean and moisten the nasal cavity Superior portion of nasal cavity is the _________ region: provides sense of smell

Air Flow From vestibule to internal nares: through superior, middle, and inferior meatuses

Meatuses Constricted passageways that produce air turbulence: _____ and _______ incoming air ______ particles

The Palates Hard palate: Soft palate: forms ______ of nasal cavity separates nasal and oral cavities Soft palate: extends _______ to hard palate divides superior nasopharynx from lower pharynx

The Nasal Mucosa Warm and humidify inhaled air for arrival at lower respiratory organs Breathing through mouth bypasses this important step

The Pharynx A chamber shared by digestive and respiratory systems Extends from internal nares to entrances to larynx and esophagus

Divisions of the Pharynx

The Nasopharynx ______ portion of the pharynx Contains pharyngeal tonsils and openings to left and right auditory tubes

The Oropharynx ______ portion of the pharynx Communicates with oral ______

The Laryngopharynx _______ portion of the pharynx Extends from hyoid bone to entrance to larynx and esophagus

What is the structure of the larynx and its role in normal breathing and production of sound?

Anatomy of the Larynx Figure 23–4

Cartilages of the Larynx 3 large, unpaired cartilages form the larynx: the ______ cartilage the _______

The Thyroid Cartilage Also called the Adam’s apple Is a _______ cartilage Forms anterior and lateral walls of larynx Ligaments attach to _____ bone, epiglottis, and laryngeal cartilages

The Cricoid Cartilage Is a ______ cartilage Form posterior portion of larynx Ligaments attach to first tracheal cartilage Articulates with arytenoid cartilages

The Epiglottis Composed of _______ cartilage Ligaments attach to ______ cartilage and hyoid bone

Cartilage Functions Prevents entry of food and liquids into respiratory tract During __________: the larynx is elevated the epiglottis folds back over glottis Thyroid and cricoid cartilages support and protect: the _______ the entrance to trachea

The Glottis Figure 23–5

Sound Production Sound Variation Air passing through glottis: _______ vocal folds produces sound waves Sound Variation Sound is varied by: tension on vocal folds voluntary muscles (position arytenoid cartilage relative to thyroid cartilage)

What is the structure of airways outside the lungs?

Anatomy of the Trachea Figure 23–6

The Trachea Also called the _________ Extends from the cricoid cartilage to the internal ridge where it branches into right and left pulmonary _________

The Tracheal Cartilages strengthen and protect airway discontinuous where trachea contacts esophagus Ends of each tracheal cartilage are connected by: an elastic ligament and __________ muscle

The Right Primary Bronchus The Primary Bronchi Right and left primary bronchi: separated by an internal ridge (the ______) The Right Primary Bronchus Is ______ in diameter than the left Descends at a _________ angle

The Lungs Left and right lungs: The base: are in left and right _______ cavities The base: inferior portion of each lung rests on superior surface of ________

The Right Lung Has _ lobes: superior, middle, and ______ separated by horizontal and oblique fissures

The Left Lung Has _ lobes: superior and inferior are separated by an oblique fissure

Relationship between Lungs and Heart Figure 23–8

Lung Shape Right lung: Left lung: is wider is displaced upward by _____ Left lung: is _______ is displaced leftward by the heart forming the cardiac notch

Extrapulmonary Bronchi The Bronchial Tree Is formed by the primary bronchi and their branches Extrapulmonary Bronchi The left and right bronchi branches _____ the lungs Intrapulmonary Bronchi Branches within the lungs

A Primary Bronchus Branches to form secondary bronchi (lobar bronchi) 1 secondary bronchus goes to each lobe

Bronchi and Lobules Figure 23–9

Secondary Bronchi Branch to form ______ bronchi, also called the segmental bronchi Each segmental bronchus: supplies air to a single bronchopulmonary segment

Bronchial Structure The walls of primary, secondary, and tertiary bronchi: contain progressively less ________ and ____ smooth muscle increasing muscular effects on airway constriction and resistance

Bronchitis _____________ of bronchial walls: causes constriction and breathing difficulty

The Bronchioles Figure 23–10

Bronchiole Structure Autonomic Control Bronchioles: have no ___________ are dominated by smooth muscle Autonomic Control Regulates smooth muscle: controls diameter of bronchioles controls airflow and resistance in lungs

Asthma Excessive stimulation and bronchoconstriction Stimulation severely restricts airflow

The Bronchioles Each tertiary bronchus branches into multiple bronchioles Bronchioles branch into terminal bronchioles: 1 tertiary bronchus forms about 6500 terminal bronchioles

Alveolar Organization Figure 23–11

Alveolar Organization Respiratory bronchioles are connected to alveoli along alveolar ducts Alveolar ducts end at alveolar sacs: common chambers connected to many individual alveoli

An Alveolus Has an extensive network of capillaries Is surrounded by ______ fibers

Alveolar Epithelium Consists of simple squamous epithelium Consists of thin, delicate Type I cells Patrolled by alveolar __________, also called dust cells Contains septal cells (Type II cells) that produce __________

Surfactant Is an _____ secretion Contains phospholipids and proteins Coats alveolar surfaces and _______ surface tension Helps diffusion of O2

Inflammation of Lobules Also called pneumonia: causes fluid to leak into alveoli compromises function of respiratory membrane

Pleural Cavities and Pleural Membranes Figure 23–8

Respiration External Respiration Internal Respiration Refers to 2 integrated processes: external respiration internal respiration External Respiration Includes all processes involved in exchanging O2 and CO2 with the environment Internal Respiration Also called cellular respiration Involves the uptake of O2 and production of CO2 within individual cells

3 Processes of External Respiration Pulmonary ventilation (breathing) Gas diffusion: across membranes and capillaries Transport of O2 and CO2: between alveolar capillaries between capillary beds in other tissues

Gas Pressure and Volume As volume decreases, pressure increases Figure 23–13

Mechanisms of Pulmonary Ventilation Figure 23–14

Respiration Causes volume changes that create changes in pressure Volume of thoracic cavity changes: with expansion or contraction of diaphragm or rib cage

The Respiratory Muscles Figure 23–16a, b

The Respiratory Muscles Figure 23–16c, d

3 Muscle Groups of Inhalation Diaphragm is the main one. Abdominal muscle system used in exhaling

Respiratory Performance and Age Figure 23–28

3 Effects of Aging on the Respiratory System Elastic tissues deteriorate: reducing lung compliance lowering vital capacity Arthritic changes: restrict chest movements limit respiratory minute volume Emphysema: affects individuals over age 50 depending on exposure to respiratory irritants (e.g., cigarette smoke)