Ch. 23 Respiratory Flashcards Preview

Human Anatomy > Ch. 23 Respiratory > Flashcards

Flashcards in Ch. 23 Respiratory Deck (30):
1

Functions

1. Gas Transport and gas exchange
2. Participation in regulating blood pH
3. Contains receptors for the sense of smell
4. Filters inhaled air
5. Produces sounds
6. Eliminates small amounts of water and heat in exhaled air

2

Upper Respiratory System/tract

nose
pharynx
associated structures

3

Lower Respiratory System/tract

larynx, trachea, bronchi, lungs
- conducting zone: nose, pharynx, larynx, trachea, bronchi, bronchioles, terminal bronchioles
* this zone filter, warm and moisten and conduct air into the lungs
- respiratory zone: includes respiratory bronchioles, alveolar ducts, alveolar sacs and alveoli, and are the main sites of gas exchange between air and blood

4

Nose

divided into external and internal portions
- external nose: skin and muscle covered portion of nose is nasal aperture, bordered laterally and inferiorly by the maxillary bones and superiorly by the nasal bones
- cartilaginous framework of the external nose: 3 larger cartilages; the unpaired septal nasal cartilage and the paired major alar cartilages and a series of smaller cartilages- the minor

5

External Nares

- entry ways into the external nose/nostrils which lead into the nasal cavities
- nasal vestibule: are cavities in the nasal cavity; skin covering this cavity contains numerous hairs, sebaceous, sweat glands
- internal nose: large cavity in the anterior aspect of the skull

6

Internal Nares/ Choanae

- portion where the internal nose merges with the external nose, and posteriorly it communicates with the pharynx through two openings
- conchae: are bony projections from the lateral wall of nasal cavity
- meatuses: series like groove-like passageways between meatuses
- both conchae and meatuses increased surface area of the nasal cavity and prevents dehydration by trapping water droplets during exhalation

7

Characterisitics

- inhaled air whirls around the conchae and meatuses, warmed by blood circulating in the capillaries
- mucus secreted by goblet cells moistens the air and traps dust particles
- drainage from the nasolacrimal ducts and secretions from the paranasal sinuses also help moisten the air
- cilia move the mucus and trapped dust particles toward the pharynx

8

Bones of Nasal Cavity

Roof: frontal, nasal, ethmoid, sphenoid
Floor: palatine, maxilla

9

Paranasal Sinuses

- paired air spaces
- derived from bones they house in
- drainage ducts to nasal cavity
Functions: sound resonance, decrease weight of skull, warm, swirl and moisten air

10

Pharynx

- funnel-shaped tube about 13cm long
Functions: as a passageway for air and food; provides a resonating chamber for speech sounds; houses the tonsils, which participate in immunological reactions against foreign invaders
- 3 anatomical regions: nasopharynx, oropharynx, laryngopharynx

11

Nasopharynx

- prosterior to nasal cavity and extends to the plane of the soft palate
- uvula hangs from the soft palate
- paired audiitory tubes connect nasopharynx to the tympanic cavity
- pharyngeal or enenoids tonsils
functions: during swallowing, soft palate and uvula elevate to block nasal cavity to prevent entry of food into lungs

12

Oropharynx

- middle portion between the soft palate and hyoid bone
- allows both swallowed food, fluid and air to pass through
- base of the tongue forms the anterior wall of the oropharynx
- two pairs of tonsils, the palatine and lingual tonsils, are found in the oropharynx
functions: allow the passage of food, fluid, air

13

Laryngopharynx

- begins at level of the hyoid bone and ends at the larynx; both a respiratory and a digestive pathway and is lined by nonkeratinized stratified squamous epithelium
- most muscles of the pharynx are innervated by nerve branches from the pharyngeal plexus supplied by the glossopharyngeal and vagus nerves

14

Larynx

- connects laryngopharynx with the trachea; lies in the midline of the neck anterior to the fourth through sixth cervical vertebrae (C4-C6)
- 3 single cartilages: thyroid cartilage, epiglottis, and cruces cartilage)
- 3 paired cartilages: arytenoid, cuneiform, corniculate cartilages
- arytenoid cartilages are the most important because they influence the positions and tensions of the vocal folds (true vocal cords)
- thyroid cartilage (Adam's apple) consists of two fused plates of hyaline cartilage that form anterior wall of larynx
- ligament that connects the thyroid cartilage to the hyoid bone just superior to it is called thyrohyoid membrane

15

Larynx (epiglotis)

- ligament that connects the thyroid cartilage to the hyoid bone just superior to it is called thyrohyoid membrane
- epiglottis composed of elastic cartilage that is covered with epithelium; "stem" of epiglottis is the tapered inferior portion that is attached to the anterior rim of thyroid cartilage and hyoid bone
- during swallowing, pharynx and larynx rise
- elevation of larynx causes epiglottis to move down and form a lid over the opening into the larynx, closing it off
- narrowed passageway through larynx is called glottis
- glottis consists of a pair of fold of mucous membrane, the vocal folds in the larynx, and space between them called the rim glottdis

16

Larynx Cartilage

- cricoid cartilage: hyaline cartilage that forms the inferior wall of the larynx; attached the trachea by the cricotracheal ligament
- thyroid cartilage is connected to the cricoid by the cricothryoid ligament
- paired arytenoid cartilage is a triangular shape composed of hyaline located posterior and superior border of cricoid cartilage
- paired corniculate cartilages; horn shaped pieces of elastic cartilage, are located at the apex of each arytenoid cartilage
- paired cuneiform cartialge, club-shaped elastic cartilages anterior to the corniculate cartilages, support the vocal folds and lateral aspects of the epiglottis

17

Vocal Folds are lined with...

- vocal folds lined with nonkeratinized stratifies squamous epithelium
- larynx inferior to the vocal folds in lines with pseudo stratified ciliated columnar epithelium, goblet cells, and basal cells; mucus secreted by these cells helps trap dust not removed in the upper passages

18

Structures of Voice Production

- mucous membrane of larynx forms two pairs of folds; a superior pair called ventricular folds (false) and an inferior pair called vocal folds (true)
- space between ventricular folds is known as the rim vestibule
- laryngeal sinus (ventricle) is a lateral expansion of the middle portion of the laryngeal cavity; bordered superiorly by the ventricular folds and inferiorly by the vocal folds
- mucous membrane of the vocal folds, lined by NKSSE, bands of elastic ligaments stretched between pieces of rigid cartilage like the strings on a guitar
- intrinsic laryngeal muscles attach to both rigid cartilage and vocal folds
- when muscles contract, they pull the elastic ligaments tight and stretch the vocal this aries the tension in the vocal folds, much like loosening or tightening a guitar string

19

Pitch in Larynx

- air passing vibrated the folds and produces sounds (phonation) by setting up sounds waves in the column of air in the pharynx, nose and mouth
- variation in the pitch of the sounds is related to the tension in vocal folds, greater the pressure of air=the louder the sounds
- intrinsic muscles contract= pull on arytenoid cartilages, which cause them to pivot and slide
- contraction of posterior cricoarytenoid muscles; moves vocal folds apart opening rim glottis
- lateral cricoarynteoid muscles moves vocal folds together closing rim glottiz
* pitch controlled by tension on the vocal folds; pulled taut= more rapid vibration and higher pitch results

20

Trachea

- tubular passageway for air that is about 12cm long
- located anterior to the esophagus and extends from larynx to superior border of 55th thoracic vertebra where it divides into right and left primary bronchi
- 3 layers of tracheal wall from deep to superficial

21

Mucosa

pseudo stratified ciliated columnar epithelium and goblet cells

22

Submucosa

areolar connective tissue that contains seromucous glands and their ducts

23

Media/middle Tunic

made of the 16-20 incomplete, horizontal rings of hyaline cartilage resemble letter head C

24

Adventitia

consists of areolar tissue that joins the trachea to surrounding tissues

25

Trachea (smooth muscle and glands)

- smooth muscle fibres of tracheal muscle and elastic connective tissue allow the diameter of trachea to change during inhalation and exhalation
- solid C-shaped cartilage rings provide a semi-rigid support so that the tracheal wall does not collapse inward and obstruct the air passageway
- smooth muscle and glands of trachea are inverted parasympathetic ally via the vagus nerves

26

Bronchi

- superior border of 5th thoracic vertebra, trachea divide into a right primary bronchus and a left primary bronchus
- right primary bronchus is more vertical, shorter, and wider than the left bronchi contain incomplete rings of cartilage and are lined by pseudo stratified ciliated columnar epithelium
- trachea divides into right and left primary bronchi there is an internal ridge called carina
- mucus membrane of carina is most sensitive area of entire larynx and trachea for triggering cough reflex
- bronchi divide to form the secondary bronchi, one for each lobe of lung

27

Bronchial Tree

- mucous membrane in bronchial tree changes from pseudo stratified ciliated columnar epithelium in bronchi to ciliated simple columnar epithelium with some goblet cells in larger bronchioles, mostly ciliated simple cubical epithelium with no goblet cells in smaller, mostly conciliated simple caboodle epithelium in terminal bronchioles
- plates of cartilage gradually replace the incomplete rings of cartilage in primary bronchi and finally disappear in distal bronchioles
- cartilage decreases= amount go smooth muscle increases; smooth muscle encircles lumen in spiral bonds; no supporting cartilage- muscle spasm (asthma attack) can close off airways

28

Lungs

- paired cone-shaped organs in thoracic cavity
- separated formic other by the heart an other structures in mediastinum; separates the thoracic cavity into two distinct chambers
- surrounded by protective, double-layered membrane (pleura and pleura cavity)
- base, apex, costal surface, mediastinual surface, hilum

29

Lobes of the Lungs

- 1 or 2 fissures divide lung into lobes
- both lungs have an oblique fissure, right lung also has a horizontal fissure; these fissures separate lobes of lungs from each other
- right primary bronchus has 3 secondary (lobar) bronchi
- left primary bronchus gives rise to 2 (lobar) bronchi
- secondary bronchi give rise to tertiary (segmental) bronchi
- segment of lung tissue that each tertiary bronchus supplies is called a bronchopulmonary segments

30

Microscopic Anatomy of Lungs

type 1 Alveolar cell: squamous epithelium, permit gas exchange
Type 2 Alveolar cell: secrete surfactant, reduces surface tension
Alveolar Macrophages: phagocytic, engulf particulates