Transcript Respiratory System - Belle Vernon Area School District

Respiratory Drill
Name two functions of the respiratory system.
What is the differences between the upper and lower
respiratory systems?
How are the conduction and respiratory zones
different?
What are the functions of the following organs…
hard palate, septum, external nares
Respiratory Drill
What is the function of the larynx?
What is the difference between true
and false vocal cords?
What forms the Adam’s apple?
Why is there only two primary
bronchi?
What is the function of the alveoli?
What does cilia do in your trachea?
What cells form cilia?
Respiratory Drill
1. Explain the role of surfactant.
2. Why are alveoli only one cell thick?
3. Trace the structures that air must
pass through when it enters the
nose.
Respiratory Drill
Name the structures the air must pass
through as it enters the lungs?
Define the following terms: Tidal volume,
inspiratory reserve volume, expiratory
reserve volume, & residual volume.
How is vital capacity different from total lung
capacity?
Why does air from the environment move into
your lungs?
Respiratory Drill
What “action” is responsible for the
movements of gases?
Where in the blood is the majority of
oxygen carried at? What is oxygen
carried by?
Where in the blood is the majority of
carbon dioxide at?
Respiratory System
Purpose
1. Gas Exchange
2. Regulation of blood pH
3. Voice production
4. Olfaction
5. Innate Immunity
Events
1. Pulmonary ventilation
2. External respiration
3. Internal respiration
Respiration – gas exchange
between external & internal
environments
I. Organs of Respiratory System
A. Series of tubes & chambers.
B. Two divisions.
First division
a. Upper respiratory
tract.
Head
Neck
b. Lower respiratory
tract.
Inside thoracic
cavity
Second division
a. Respiratory Zone
Structures of gas
exchange.
b. Conduction Zone –
conducts air.
C. Nose – initial receiving chamber
1. External Nares or nostrils
2. Septum
3. Vestibule
4. Nasal Cavity
a. paranasal sinuses – small ducts lines with
mucus
b. Sinusitis
5. Hard Palate
D. Pharynx
1. Receives air from the
internal nares.
2. Composed of skeletal
muscle.
3. Lined with mucus.
4. Back of nasal cavity to the
larynx:
a. Nasopharynx
(auditory tubes)
b. Oropharynx
c. Larygnopharynx
E. Larynx – voice box
1. Connects pharynx to
trachea.
2. Thyroid Cartilage
Adam’s apple.
3. Cricoid Cartilage
4. Epiglottic Cartilage
5. False Vocal Cords
6. True Vocal Cords
7. Epiglottis
F. Trachea – wind pipe
1. 12 cm long.
2. Supported by c-shaped rings,
smooth muscle, & elastic fibers.
3. Lined with ciliated mucous
membrane.
Mucus secreting cells
(PSCC).
4. Pseudostratified columnar cells.
Cilia beats in synch to
removed trapped particles
in mucus.
Sputum – expelled or
swallowed.
Mucocillary transporting
system- prevents toxins
from reaching the aveloi .
G. Bronchial Tree
1. Primary (main)– Right &
Left
2. Secondary Bronchi (Lobar)
3. Tertiary bronchi
(segmental)
4. Bronchioles
a. terminal
b. respiratory
5. Alveolar Ducts
6. Alveoli
7. Alveolar sacs
H. Alveoli – 300-500 million/ lung.
1. Increase Surface area (size of tennis court 70 m2).
2. Thin layer of watery fluid which is necessary for gas
exchange (moisture).
3. Moisture causes surface tension (alveloi tissues stick
together).
4. Surfactant – detergent like lipids – counteracts
tension.
5. Respiratory Membrane – site of gas exchange in the
lungs
7. Pre-mature babies – no surfactant.
a. Run a chance of suffocation.
b. Force air in & out.
c. Exhausted.
d. Respiratory Disease Syndrome (RDS) or Hyaline
Membrane Disease (HMD).
e. 25,000/ yr die
8. Capillaries
a. Walls of aveoli in close contact with capillary walls.
b. Thin membrane for gas diffusion .5um.
I. Lungs – Gas exchange between atmosphere & bloodstream.
1. Characteristics
a. Soft.
b. Spongy.
c. Shaped like a cone.
d. Root - attachment to trachea & heart.
2. Serous Membrane (pleura)
a. Parietal Pleura – lines the thoraic wall.
b. Visceral – line outer surface of lings.
c. Pleural Cavity – space between parietal & visceral.
d. Pleural Fluid – Lubricates surface to reduce friction
created from breathing.
e. Pleurosy – Reduction of fluid & membrane rubs against.
3. Divisions
a. Lobes – smaller compartments
1. Right Lung – 3 lobes – larger
2. Left Lung – 2 lobes
3. Fissures – divides lobes
b. Segments – supplied by a smaller branch of bronchi.
c. Lobules – receives a single bronchiole, arteriole,
venule.
II. Mechanisms of Breathing
A. Inspiration – Contraction of the respiratory muscle to
expand the volume of the thorax & lungs.
1. Diaphragm pushes down.
2. Extends intercostals & raises the rib cage.
3. Resulting in the expansion of the thoraic cavity.
4. Lung surface is pulled outward.
5. Volume increases.
6. Alveoli pressure falls below atmosphere pressure (13 mm below atmosphere).
7. Air rushes in.
B. Expiration
1. No muscle activity, but recoil of elastic tissue.
2. Forced expiration requires muscle contraction to push air
outward.
a. Diaphragm & external intercostals muscles relax.
b. Thoraic cavity decreases in size.
c. Pleural cavity pressure increases.
d. Alveoli pressure becomes greater then the
atmosphere.
e. Air flows outward.
Mechanisms of Breathing
C. Respiratory Volume
1. Sleeping, exercise (light or heavy) physical difference,
height, age, sex, health.
2. Spirometer – measures respiratory volumes.
3. Average 500 ml/ breath.
Respiratory Volume
III. Exchange of Gases
A. Differences of oxygen & Carbon dioxide at the alveoi & blood
(external respiration), blood & cells (internal respiration).
B. Oxygen & Carbon dioxide will follow diffusion by moving from
areas of greater concentration & areas of lesser.
C.
Nitrogen – 78%
Oxygen - 21 %
Carbon - .04%
Each create a partial pressure
D. Each gas will diffuse at own rate based on partial pressure.
E.
External Respiration
Alveoli & Blood stream
1.
Greater partial pressure on
oxygen in the alveoli then
blood.
2.
Establishes a pressure gradient
3.
98% of oxygen bind to
hemoglobin (oxyhemoglobin).
4.
2% in plasma.
5.
Carbon dioxide partial pressure
is greater in the blood then
alveoli.
6.
Establishes a pressure gradient
7.
Carbon dioxide leaves the blood
F. Internal Respiration
1. Relies on pressure gradient in capillaries & interstitial fluid.
2. 70% of Carbon Dioxide in blood changes to bicarbonate ions
(HCO3)
3. 23% of carbon dioxide binds with hemoglobin.
4. 7% remains dissolved.
5. CO2 + H20 (Carbonic anhydrase) -> H2CO3 -> HCO3 (Bicarbonate ions)
+H.
6. Once changed, moves to plasma & remain in RBC by binding to
hemoglobin.
7. Remove at the capillaries in the lungs.
IV. Control of Breathing.
A. Rate & deepness is control by the
respiratory center is in the brain.
B. Respiratory Center
1. Medulla Rhythmicity Center.
a. Ventral – only active
when needing a more
forceful breath.
b. Dorsal – Normal
breathing:
Fires for inhalation.
No firing for exhaling.
C. Pneumotaxic Area (Upper pons) –
Decreases the rate
1. Strong short duration – decreases
breathing rate.
2. Weak – Long durations –
increases breathing rate.
D. Apneuatic Area (lower Pons)
Sends signal to dorsal respiratory to
prolong inspiration.
E. Factors that effect breathing.
1. Chemical changes in the blood.
(Chemoreceptors)
2. Stretch of lungs.
(Baroreceptors)
3. Mental state
V. Diseases
1. Asthma
a. Pulmonary edema (Fluid accumulation in lungs)
1. Inflammation, spasms of smooth muscle in
small bronchi.
2. . Emphysema
Alveoli & alveoli ducts are destroyed by
leukocytes.
Causes: smoking, pollutants, dust.
3. Pnuemonia
Infection of alveoli by bacteria or virus.
Accumulation of fluid within the alveoli which fills with
pathogens.
4. Lung cancer – Number 1 killer in America.