Respiratory System Exam 3 Flashcards
What contributes to homeostasis functions of the respiratory system
Move air into and out of lungs
Gas Exchange
-Intake of O2 -> deliver to cells
-Remove CO2 from body cells
Regulate blood pH
Smell, vocal sounds, filter air
Excrete small amounts of water and heat
What disrupts homeostasis functions of the respiratory system
Cell death from O2 starvation
Build up of waste products
Structural Classification of respiratory system
Upper respiratory track
-Nose
-Nasal Cavity
-Pharynx
Lower respiratory track
-Larynx
-Trachea
-Bronchus
-Lungs
What are the two functional classification sections of the respiratory system
Conducting Zone
Respiratory Zone
What does the Conducting Zone do
Conducts air into lungs
-Consists of nose, pharynx, larynx, trachea, bronchi, bronchioles, and terminal bronchioles
What does the Respiratory Zone do
Main site of gas exchange
-Consists of respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli
What are the functions of the nose and nasal cavity
Warm, moisten, filter incoming air
Detect olfactory stimuli
Modify speech vibrations (resonance chambers)
What does the epiglottis flap do
At rest it is upright -> allow it to pass into larynx and lungs
Eating the flap cover the top of the windpipe -> food does not go into larynx or lungs
Pharynx
Known as throat
Passageway for air and food
Resonating chamber
Has Tonsils (lymphoid tissue)
Larynx
Protect lower airways (close larynx to allow food to pass)
Swallowing
Phonation (vocal cords)
Made up of hyoid bone & cartilage
Has Adams apple
Trachea: composed of, connection, location
Bony tube anterior to esophagus
16-20 C-shaped hyaline cartilage rings
Flexible (does not collapse)
Posterior soft tissue (expand esophagus)
Connects larynx to lungs
Divides right and left primary bronchi
What are the smaller divisions of the lungs
Lung -> lobes -> segment -> lobules
(Right has three lobes, left has two)
Bronchial Tree: composed of, epithelium, cells
-Amount of cartilage decreases and smooth muscle increases further down track (creates more branches)
—Muscle spams produce bronchoconstriction
-Mucous membrane in bronchial tree changes
—From different ciliated epithelium to mostly nonciliated epithelium in terminal bronchioles
-Presence of Globet Cells
Bronchi Regulation: autonomic control, bronchodilation, bronchoconstriction
Autonomic Control
-Regulates smooth muscle
Bronchodilation
-dilate airways
-caused by sympathetic ANS activation
-reduces resistance
Bronchoconstriction
-caused by parasympathetic system ANS ACh activation and histamine release (allergic reactions)
Bronchopulmonary Segments: tertiary segment, lobule, terminal
-Tertiary segmental bronchi -> supply air to segment (has lobules)
-Lobule have branch from terminal bronchioles that connect to respiratory bronchioles
-Terminal bronchioles represent END of conducting zone
Respiratory Bronchioles: components and alveoli cells
Lead to alveolar ducts -> ducts end at sacs composed of alveoli
Alveoli are small air-filled chambers where gas exchange between air and blood happens
(grapes and vine)
Lobules of the lungs: pulmonary, composed of, terminal, aveoli
-Pulmonary Lobule is functional unit of lung
-Lobule has lymphatic vessel, arteriole, venule, terminal bronchiole
-Terminal bronchioles originate respiratory bronchioles which have alveoli budding from walls (gas exchange)
-Aveoli surrounded by pulmonary capillaries
Epithelium of Alveoli: Type II Cells
AKA: Granular Pneumocytes or Septal Cells
-Thicker and rounded cells w/ inclusion bodies or cytosomes
-Secrete surfactant (reduce surface tension, easier for alveoli to expand)
Epithelium of Alveoli: Type I Cells
AKA: Pneumocytes
-Flat squamous cells w/ large cytoplasmic extensions
-Thin barrier permeable to gases (gas exchange main site)
Epithelium of Alveoli: Alveolar Macrophages or Dust Cells
Remove dust particles
Remove debris from alveolar sacs
External Respiration
Conversion of deoxygenated blood into oxygenated blood (only in lungs)
Pulmonary gas exchange by simple diffusion
-O2 from alveolar air -> O2 into blood
-unloads CO2 from blood -> CO2 into alveolar air
CO2 eliminated from blood during exhalation
Gas exchange in external respiration: exchange of O2 and CO2
Exchange of O2
-partial pressure of O2 in air lower than blood
-O2 diffuses from air into RBC
Exchange of CO2
partial pressure of CO2 in air lower than in blood
CO2 diffuses from RBC to air in lungs
Internal Respiration
Exchanges of gas between systemic circulation and tissue cells -> systemic gas exchange
Blood picks up CO2 from tissue cells and unloads O2 into tissue cells
Gas exchange in internal respiration: exchange of O2 and CO2
Exchange of O2
pressure of O2 in interstitial fluid is lower than blood
O2 diffuses from blood into tissue
Exchange of CO2
pressure of Co2 in blood is lower than in interstitial fluid
CO2 diffuses from tissue cells into RBC
Transport of Oxygen: plasma and oxyhemoglobin
only 2% of O2 dissolved in plasma
98% as Oxyhemoglobin of O2 is bound to Hb in RBC
-only dissolved O2 portion can diffuse out of blood into cell
-O2 must bind and dissociate from heme in Hb
Hemoglobin Saturation
-amount O2 bound to Hb related to pressure of O2
-Hb saturation -> % of heme units in Hb that contain bound O2
-↑ pO2 increases % of Hb saturation
Factors affecting Hb saturation
-Decreases in pH*
-Increase in pCO2*
-Increase in temperature
-Increase in DPG in erythrocytes
CO2 is by product of aerobic metabolism. What are the three ways in which CO2 can be transported in the bloodstream
Dissolved in plasma
-diffuses into alveolar air and exhaled
Bound to Hb
Converted to Carbonic Acid
-Rxn occurs un plasma and in RBC
-Faster in RBC bc of enzyme carbonic anhydrase
Gas exchange in tissue
Blood picks up CO2 from tissue cells and unloads O2 into tissue cells
HCO3- out and Cl- in
Gas exchange in alveoli
Blood picks up O2 from air and unloads CO2 into air
HCO3- in and Cl- out
Pulmonary Ventilation
Air into lungs -> pressure in lungs < pressure in atm
Air out of lungs -> pressure in lungs > pressure in atm
Inhalation is an active process
-Contract of pec muscles
-Diaphragm contracts -> pulls bottom of cavity down
-Ribcage moves up and out (more room lowers pressure to get air in)
Exhalation if a passive process
Muscles and diaphragm relax
Rib drop-down -> cavity decreases (less room, air out)
Respiratory Center: contains what, what are the three areas
Contains motor neurons that control respiratory muscles
Based on function area is divided into three areas
-Medullary rhythmicity (in medulla oblongata)
-Pneumotaxic area (in pons)
-Apneustic area (in pons)
Medullary Respiratory or Rhythmicity Area
controls basic rhythm of respiration
Inspiratory or Dorsal respiratory group (DRG)
Functions in quiet breathing
Neurons fire automatically
Expiratory or Ventral respiratory group (VRG)
functions only in forced breathing
Medullary Rhythmicity Area
impulses to the external and internal intercostal muscles and to diaphragm -> different nerves involved
Quiet breathing or inspiration: Active and Inactive
Active (2 seconds)
-Diaphragm and external intercostals actively contract
-Normal quiet inhalation
Inactive (3 seconds)
-Diaphragm and external intercostals relax, followed by recoil of chest wall and lungs
-Normal quiet exhalation
Inspiratory area establishes the _______ ________ of breathing
basic rhythm
Forceful Breathing
Inspiratory Area -> muscles contract -> forceful inhale
Inspiratory Area activates expiratory area -> internal intercostal and ab muscles contract -> forceful exhale
Apneustic Areas
-Helps turn off inspiratory area, limit inspiration to prevent overexpansion of lungs
-Transmits inhibitory impulses to inspiratory area to shorten duration of inhalation (more active = rapid rate)
Pneumotaxic Areas
-Send stimulatory impulses to inspiratory area
-Activates area and prolongs inhalation
-Stimulation results in long and deep inhalation
-Signals from apneustic area are overridden when area is active
Rhythm of respiration can by modified by inputs from
brain
peripheral & central receptors
other factors temp, irritation of airways
Regulation of Respiratory Center
-Cerebral complex has connections with respiratory center
-Voluntary control is protective -> prevent water or gas in
-Refuse to breathe -> breath resume from pressure or pass out and breath resume
