The Respiratory System

1
The Respiratory System

• Chapter 10

2
The Respiratory System

• _________ Respiratory Tract (structures outside
  of the lungs)
• Nostrils
• Nasal passages
• Pharynx
• Larynx
• Trachea
• _________ Respiratory Tract (structures within
  the lungs)
• Bronchi
• Bronchioles
• Alveolar ducts
• Alveoli

3
Intro to the Respiratory System

• The primary function of the respiratory system is
  to bring ___________ into the body and to carry
  _________ __________ out of body.
• Respiratory system works together with the
  cardiovascular system!
• Secondary functions
• Phonation (voice production)
• Regulation of body temperature
• Regulation of acid-base balance
• Sense of smell

4
Two types of Respiration

• ____________ Respiration
• Occurs in capillaries of pulmonary circ.
• Is the exchange of oxygen and carbon dioxide
  between the air that is inhaled into the lungs
  and the blood flowing through the pulmonary
  capillaries.
• ____________ Respiration
• Occurs in capillaries of systemic circ.
• Is the exchange of oxygen and carbon dioxide
  between the blood in the systemic capillaries and
  all of the cells and tissues of the body.

5
Voice Production

• Also called ____________.
• Begins in the larynx (voice box).
• Two bands called the _______ _______ (or vocal
  folds) stretch across the lumen of the larynx and
  vibrate as air passes over them.
• Thorax, nose, mouth, pharynx, and sinuses may
  contribute to the vocal sounds.

6
Body Temperature Regulation

• Cold conditions
• Superficial blood vessels under the epithelium of
  the nasal passages helps warm inhaled air before
  it reaches the lungs.
• Keeps chilled air from circulating through the
  lungs and causing hypothermia.
• Hot Conditions
• Aids in cooling through panting.
• Rapid respiration movements caused during panting
  cause increased evaporation of fluid from the
  lining of the respiratory passages and mouth,
  which helps to cool the blood vessels under the
  epithelium.

7
Acid Base Balance

• Important homeostatic mechanism in the body.
• Lower the pH, the more _________ the environment
• Higher the pH, the more _________ the
  environment.
• Normal pH of the blood is ______ (acceptable
  range of 7.35-7.45).

• CO2 (carbon dioxide) is considered an acid in
  the bloodstream.
• The higher the CO2, the lower the blood pH, the
  more acidic the blood.
• Respiratory system can alter CO2 content in the
  blood by adjusting how fast air is breathed in
  and out.

8
Sense of Smell

• Also called the _________ sense.
• Many animals have less sensitive eyesight than
  humans, but a highly sensitive sense of smell.
• Receptors are contained in two patches of sensory
  epithelium located up high in the nasal passages.
• Olfactory cells are mixed with supporting cells
  in the patches.
• Hairlike processes of the olfactory cells project
  up into the mucous layer that covers the nasal
  epithelium
• When odor molecules dissolve in the mucus and
  contact the sensory processes, nerve impulses are
  generated that travel to the brain and are
  interpreted as smells.

9
Upper Respiratory Tract

• Nostrils
• Nasal passages
• Pharynx (throat)
• Larynx (voice box)
• Trachea (wind pipe)

10
The Nose

• ____________ nostrils external openings of the
  respiratory tube
• ___________ ______________ between the nostrils
  and pharynx
• Nasal __________- separates the left nasal
  passage from the right
• Hard and Soft __________- separate the nasal
  passages from the mouth.
• Contain _____________ (nasal conchae) thin,
  scroll-like bones covered with nasal epithelium
  that occupy most of the lumen of the nasal
  passages.
• 2 sets (dorsal and ventral) that divide each
  nasal passage into 3 main passageways
• Each passageway is called a ____________.
• Ventral, middle, dorsal and common

11
(No Transcript)
12
Lining of the nasal passages

• Lined with _____________ _____________ epithelium
• _________ project from the cell surfaces up into
  a layer of mucus
• Mucus is secreted by _________ cells.
• Extensive complex of large blood vessels lies
  just beneath the nasal epithelium.

13
Sinuses

• _____________ of the nasal passages that are
  contained within spaces in certain skull bones.
• Each sinus is named after the skull bone that
  houses it.
• Most animals have two _________ sinuses and
  __________ sinuses.
• Sinuses have same ciliated lining as the nasal
  passages. Cilia keep fluid and debris from
  accumulating in sinuses and obstructing the
  openings of the nasal passages by sweeping it
  down into the nasal passages.

14
Sinusitis

• Inflammation of the sinuses. Due to infection,
  allergies, tumors, etc.
• Openings into nasal passages swell shut or become
  clogged with inflammatory debris
• Fluid in sinuses cannot be passed ? ?pressure ?
  pain
• Build up of pressure can be very uncomfortable
  for the animal.
• Can be treated with antibiotics and
  decongestants, but if ineffective, a hole may
  need to be drilled into the sinus to allow
  drainage.

15
Pharynx (Throat)

• Common passageway for both _____________ and
  _____________ systems.
• Rostral end is divided into
• _______pharynx (respiratory passageway, dorsal)
• _______pharynx (digestive passageway, ventral)
• Divided by the soft palate
• Caudal end is divided into
• ___________ (digestive passageway, dorsal)
• ___________ (respiratory passageway, ventral)

16
Larynx

• Commonly called the voice box
• Short, irregular tube that connects the _________
  with the trachea.
• Made of segments of ___________ that are
  connected to each other and the surrounding
  tissues by muscles.
• Supported by the hyoid bone.
• Cartilage components epiglottis, arytenoid
  cartilages, thyroid cartilage, cricoid cartilage

17
Laryngeal Cartilages

• Epiglottis
• Single, leaf-shaped projects forward from the
  ventral portion of the larynx
• During swallowing, the epiglottis is pulled back
  to cover the opening of the larynx

18
Laryngeal Cartilages

• Arytenoid cartilages
• Paired attachment site of the vocal cords
• Muscles adjust the tension of the vocal cords by
  moving the cartilages.
• Arytenoid cartilages and the vocal cords form the
  boundaries of the _________-the opening into the
  larynx.

19
Laryngeal Cartilages

• Thyroid cartilages
• Shaped as a V that forms and supports the ventral
  portion of the larynx.
• Cricoid cartilage
• Ring-shaped, helps form and support the caudal
  portion of the larynx.

20
Breathing and Swallowing

• Because it is a common passageway that must allow
  both breathing and swallowing, delicate reflexes
  control the actions of the muscles around the
  pharynx
• Larynx and pharynx work together to prevent
  swallowing from interfering with breathing and
  vice versa.
• Swallowing
• Breathing stops
• Opening to the larynx is covered (by epiglottis)
• Moving of material to be swallowed to rear of
  pharynx
• Esophagus opens and material moves into it
• Larynx reopens
• Breathing resumes

21
Laryngeal Functions

• 1. Voice Production
• Originates at vocal cords in the larynx.
• Vocal cords are two bands attached to arytenoid
  cartilages that stretch across the lumen of the
  larynx.
• As air passes over vocal cords, they vibrate and
  produce sounds.
• Muscles attached to arytenoid cartilages control
  the tension of the vocal cords.
• Lessening tension of the vocal cords allows for
  __________ pitched sounds.
• Tightening of the vocal cords allows for
  _________ pitched sounds.

22
Laryngeal Functions

• 2. Prevention of Foreign material being inhaled.
• During swallowing, muscle contractions pull the
  larynx forward and fold the epiglottis back over
  its opening.
• 3. Control of airflow to and from lungs.
• Adjustments in the size of the glottis.
• Closure of glottis necessary to cough, strain
  (lifting, defecation, urination, parturition)

23
Coughing

• Cough is generated behind a closed glottis.
• Breathing muscles contract, compressing the
  thorax.
• Builds pressure behind the closed glottis.
• When glottis suddenly opens, the forceful release
  of air results in a cough.
• Purpose of coughing is to clear mucus and other
  matter from lower respiratory passages.

24
Other terms

• __________- similar to a cough, but originates in
  the nasal passages, burst of air is directed
  through the nose and mouth in effort to eliminate
  the irritant.
• __________- slow, deep breath taken through a
  wide-open mouth. May be stimulated by slight
  decrease in oxygen levels, drowsiness, fatigue,
  and boredom.
• __________- slightly deeper than normal breath.
  May serve to expand lungs more than normal. May
  hear sighing patient under anesthesia.
• __________- spasmodic contractions of the
  diaphragm accompanied by sudden closure of the
  glottis. Usually self-limiting