Download Respiratory System Overview

Respiratory System
Internal Respiration
• Internal respiration is the process by
which the gases in the air that has already
been drawn into the lungs by external
respiration are exchanged with gases in
the blood/tissues so that carbon dioxide
(CO2) is removed from the blood and
replaced with oxygen (O2).
External Respiration
• External respiration concerns the
process by which external air is drawn into
the body in order to supply the body with
oxygen gas, and the (used) air is expelled
from the lungs in order to remove carbon
dioxide from to body
Cellular Respiration
• Internal
respiration is
important to
cells because
without
oxygen, all
body functions
would cease
due to a lack of
ATP
Main Function
• Gas Exchange
– To work closely
with the
cardiovascular
system to supply
the body with
oxygen and to
dispose of carbon
dioxide
Organs Include
1. Nose
2. Pharynx
3. Larynx
4. Trachea
5. Bronchi
– And their
smaller
branches
6. Lungs
– Containing
alveoli
(terminal sacs)
The Nose
• Externally visible
– Nostrils – External
Nares
– Internally – Nasal
Cavity
– Divided by nasal
septum
– Olfactory receptors in
the superior cavity in
the mucosa
Function of Nose
• Mucosa lining rests on thin walled veins that warm the air
• Mucous produced by the mucosa, moistens the air and traps
bacteria and other particulates
Pharynx
• 13cm muscular
passageway
(Throat)
• Food and air
passage
– NasopharynxSuperior
– Oropharynxcentral
– LaryngopharynxInferior
Pharynx
• Tonsils are
located in the
pharynx
– Pharangeal or
Adenoids
(superior)
– Palatine
(oropharynx)
– Lingual (base of
tongue)
Epiglottis
• epiglottis guards the
entrance of the glottis
• normally pointed upward
during breathing with its
underside functioning as
part of the pharynx
• during swallowing
elevation of the hyoid
bone draws the larynx
upward; and prevents
food from going into the
trachea; instead directs it
to the esophagus
Larynx
• AKA Voice box, routes air,
role in speech
• Inferior to pharynx
• Eight rigid hyaline cartilage
– Largest is Thyroid
cartilage (Adam’s
Apple)
– Protrusion angel 90˚ in
males and 120˚ in
females
• Cartilage flap – Epiglottis
protects opening
Larynx
• Mucous Membrane
forms Vocal folds
(vocal cords)
– allow us to speak
• Glottis - Slit-like
passageway between
the vocal folds
Trachea
• Windpipe
• Goes to the 5th
Thoracic Vertebrae
• Reinforced with Cshaped cartilage rings
to keep it open
anteriorly and allow
flexibility for food to
pass through the
esophagus posteriorly
Main Bronchi
• Division of the
trachea
• Runs obliquely
• Ends at the hilus
(medial depression of
the lung)
– The right is wider and
shorter and more often
the site of inhaled
objects
Bronchioles
• Primary bronchi
subdivide into
smaller branches
• Bronchial Tree
– Secondary
Bronchi
– Tertiary Bronchi
– Then Bronchioles
Alveoli
• Small cavity or air sac
– Millions of clustered
alveoli look like
bunches of grapes
• Site of gas exchange
• Make up a bulk of the
lungs
– Also stroma which is
elastic
Diaphragm
• sheet of internal
muscle that extends
across the bottom of
the rib cage
• The diaphragm
separates the thoracic
cavity (heart, lungs &
ribs) from the
abdominal cavity and
performs an important
function in respiration.
Diaphragm
• Inspiration: During inhalation, the
diaphragm contracts, thus enlarging the
thoracic cavity (the external intercostal
muscles also participate in this
enlargement). This reduces intra-thoracic
pressure: In other words, enlarging the
cavity creates suction that draws air into
the lungs
Diaphragm
• Expiration: When the diaphragm relaxes,
air is exhaled by elastic recoil of the lung
and the tissues lining the thoracic cavity in
conjunction with the abdominal muscles
Gas Exchange
• Diffusion, the
spontaneous
movement of gases,
without the use of any
energy or effort by the
body, happens
between the gas in
the alveoli and the
blood in the
capillaries in the
lungs.
CO2 and O2
• The hemoglobin molecule is the primary
transporter of oxygen
• Oxygen from the air enters the blood, and
carbon dioxide from the body trades places with
the oxygen by leaving the blood and entering the
alveoli.
• Carbon dioxide is then exhaled out of the lungs.
• Oxygen must enter the blood and carbon dioxide
must leave the blood at a regular rate for our
body to function correctly.
Pulmonary Circulation
• The Pulmonary circulation is the portion of
the cardiovascular system which
transports oxygen-depleted blood away
from the heart, to the lungs, and returns
oxygenated blood back to the heart.
Systemic Circulation
• Systemic circulation is the portion of the
cardiovascular system which transports
oxygenated blood away from the heart, to
the rest of the body, and returns oxygendepleted blood back to the heart.
• Carbon Dioxide is picked up along the way
and is also carried back to the heart to be
exhaled through the lungs.
Bone Structures
• Conchae- Increase
surface area of
mucosa and create
turbulance
• Palate- Separates
from oral cavity
– Hard palate (bone ) is
anterior
– Soft palate(tissue) is
posterior
Cleft Palate
• Genetic Defect
• Bones do not
fuse medially
• Causes
Problems:
– Breathing
– Chewing
– Speaking
Paranasal Sinuses
• Surround the
nasal cavity
• Located in
Bones:
–
–
–
–
Frontal
Sphenoid
Ethmoid
Maxillary
Function of Sinuses
• Lighten the skull
• Resonance for
speech
• Produce
mucous
• Nasolacrimal
ducts
– Drain tears from
eyes
Rhinitis, Sinusitis, Sinus Headache
• Inflammation of
the nasal mucosa
– Virus
– Allergens
• Mucosa is
continuous so that
these infections
often spread
Lungs
• Occupy entire thoracic
cavity (except
mediastinum where the
heart is)
• Narrow superior portion
(apex) is deep to
clavicle
• Broad base rests on
the diaphragm
• Left lung = 2 lobes
• Right lung = 3 lobes
Lungs
• Surface covering is
visceral serosa called
Pulmonary Pleura
• Walls of the cavity are
covered with parietal
pleura
• Pleural fluid reduces
friction during
breathing movements
Pleurisy
• Inflammation of
the pleura due to
decreased
secretion of
pleural fluid
• Pain with each
breath
• Excess fluid may
hinder breathing
Respiratory Membrane
• Thin squamous
epithelial cells
• Alveolar pores
connect sacs
• External surfaces
have a “cobweb” of
capillaries
• Respiratory
Membrane is the
Air / Blood barrier
Airway Obstruction
• Heimlich Maneuver
– Physical Procedure
where someone
assists in dislodging a
blockage
• Tracheostomy
– Surgical Procedure
cuts a new opening