respiratory system

respiratory membrane consists of four layers

1. a layer of type I and type II alveolar cells and associated alveolar macrophages that consitutes the alveolar wall 2. an epithelial basement membrane underlying the alveolar wall 3. a capillary basement membrane that is often fused to the epithelial basement membrane 4. the capillary endothelium

layers of the tracheal wall from deep to superficial are...

1. mucosa 2. submucosa 3. hyaline cartilage 4. adventitia

structures that air passes through during inpiration

1. nose 2. pharynx 3. larynx 4. trachea 5. primary bronchi 6. secondary bronchi 7. tertiary bronchi 8. bronchioles 9. terminal bronchioles

functions of external nose

1. warming, moistening, and filtering incoming air; 2. detecting olfactory stimuli 3. modifying speech vibrations as they pass through the large, hollow resonating chambers

surfactant

a complex mixture of phospholipids and lipoproteins. lowers the surface tension of alveolar fluid, which reduces the tendency of alveoli to collapse

alveolus

a cupshaped outpuching lined by simple squamous epithelium and supported by a thin elastic basement membrane

pharynx

a funnel shpaed tube that starts at the internal nares and extends to the level of the cricoid cartialge, the most inferior cartilage of the larynx

pharynx functions

a passageway for air and food, provides a resonating chamber for speech sunds, and houses the tonsils which participate in immunological reactions agains foreign invaders

cricoid cartilage

a ring of hyaline cartilage that forms the inferior wall of the larynx. is the landmark for making an emergency airway called a tracheotomy

mucosa of the trachea consists of....

an epithelial layer of pseudostratified ciliated columnar epithelium

type II alveolar cells (septal cells)

are fewer in numbers and are found between type I alveolar cells. secrete alveolar fluid, which keeps the surface between the cells and the air moist

mucous membrane in the bronchial tree changes from pseudostratified ciliated columnar epithelium in the primary bronchi, secondary bronchi and tertiary bronchi to ciliated simple columnar epithelium with some goblet cells in larger bronchioles to mostly ciliated simple cuboidal epithelium with no goblet cells in smaller bronchioles to mostly nonciliated simple cuboidal epithelium in terminal bronchioles

as the amount of cartilage decreases, the amount of smooth muscle increases

laryngopharynx

begins at the level of the hyoid bone. opens into the esophagus posteriorly and the larynx anteriorly. is both a respiratory and a digestive pathway and is lined by nonkeratinized stratified squamous epithelium

what functions do respiratory system and cardiovascular system have in common?

both cooperate to supply O2 and eliminate CO2. respiratory system provides for gas exchange-intake of O2 and elimination of CO2- and the cardiovascular system transports blood containing the gases between the lungs and body cells. the respiratory system also helps regulate blood pH, if either system were to fail it would disrupt homeostasis and rapid death of cells from oxygen starvation and buildup of waste products

during exercise, activity in the sympathetic division of the ANS increases and the adrenal medulla releases the hormones epinephrine and norepeinephrine

both of these events cause relaxation of smooth muscle in the bronchioles which dilates the airways. because air reaches the alveoli more quickly, lung ventilation improves. the parasympathetic division of the ANS and mediators of allergic reactions such as histamine have the opposite effect, causing contraction of bronchiolar smooth muscle, which results in constriction of distal bronchioles

structure of upper respiratory system

conists of two parts: upper respiratory system- includes nose, pharynx, and associated structures lower respiratory system- includes larynx, trachea, bronchi, and lungs

glottis

consists of a pair of folds of mucous membrane the vocal folds in the larynx and the space between them called the rima glottidis. closing of the larynx in this way during swallowing routes liquids and foods into the esophagus and keeps them out of the larynx and airways

thyroid cartilage

consists of two fused plates of hyaline cartialge that form the anterior wall of the larynx and give it a triangular shape

function of upper respiratory system

consists of two parts: conducting zone- consists of a series of interconnecting cavities and tubes both outside and within the lungs. include nose, pharynx, larynx, trachea, bronchi, bronchioles and terminal bronchioles, their function is to filter, warm, and moisten air and conduct it into the lungs respiratory zone- consists of tissues within the lungs where gas exchange occurs. include the respiratory bronchioles, alveolar ducts, alveolar sacs and alveoli; they are the main sites of gas exchange between air and blood

nasal septum

divides the nasal cavity into right and left sides

pleural membrane

double layered serous membrane that encloses each lung

lobules

each is wrapped in elastic connective tissue and contains a lymphatic vesel, an arteriole, a venule, and a branch from a terminal bronchiole

function of nasopharynx

exchanges small amounts of air with the auditory tubes to equalize air pressure between the pharynx and the middle ear

alar cartilages

form a portion of the walls of the nostrils

soft palate

forms the posterior portion of the roof of the mouth, is an arch shaped muscular partition between the nasopharynx and oropharynx that is lined by mucous membrane

left primary bronchus

goes into the left lung

right primary bronchus

goes into the right lung, is more vertical , shorter, and wider than the left

corniculate cartilages

horn shaped pieces of elastic cartilage, are located at the apex of each arytenoid cartilage

a unique feature of pulmonary blood vessels is their constriction in response to localized hypoxia.

in all other body tissues, hypoxia causes dilation of blood vessels to increase blood flow. in the lungs however, vasoconstriction in response to hypoxia diverts pulmonary blood from poorly ventilated areas of the lungs to well ventilated regions, known as ventilation-perfustion coupling

lateral nasal cartilages

inferior to the nasal bones

internal nose

large cavity beyond the nasal vestibule in the anterior aspect of the skull that lies inferior to the nasal bone and uperior to the mouth. is lined with muscle and mucous membrane

epiglottis

large, leaf shaped piece of elastic cartilage that is covered with epithelium, during swallowing the pharynx and larynx rise. elevation of the pharynx widens it to receive food or drink; elevation of the larynx causes the epiglottis to move down and form a lid over the glottis closing it off.

lining of the larynx superior to vocal folds consists of....

nonkeratinized stratified squamous epithelium

oropharynx is lined with....

nonkeratinized stratified squamous epithelium

oropharynx

one opening called the fauces, this portion of the pharynx has both respiratory and digestive functions serving as a common passageway for air, food, and drink.

trachea

or windpipe, is a tubular passageway for air. is located anterior to the esophagus of the tfifth thoracic vertebra where it divides into right and left primary bronchi.

lungs

paired cone shaped organs in the thoracic cavity

septal nasal cartilage

part of the cartilaginous framework of the external nose, forms the anterior portion of the nasal septum

nasopharynx is lined with....

pseudostratified ciliated columnar epithelium

primary bronchi is lined with...

pseudostratified ciliated columnar epithelium

lining of the larynx inferior to vocal folds...

pseudostratified ciliated columnar epithelium consisting of ciliated columnar cells, goblet cells and basal cells

the lungs receive blood via two sets of arteries:

pulmonary arteries and bronchial arteries

larynx

short passageway that connects the laryngopharynx with the trachea.

type I alveolar cells

simple squamous epithelial cells that form a nearly continuous lining of the alveolar wall, main sites of gas exchange

what structural and functional features are different in the upper and lower respiratory systems?

structurally different: upper respiratory system contains the nose, pharynx, and associated structures, the lower respiratory system consists of larynx, trachea, bronchi, and lungs. functionally different: upper respiratory system will filter, warm, and moisten air and conduct it into the lungs, lower respiratory system is where gas exchange occurs between air and blood

structure and function of external nose

structure: external nose is the portion of the nose that is visible, consists of a supporting framework of bone and hyaline cartilage covered with muscle and skin and lined by a mucous membrane. functions: 1. warming, moistening, and filtering incoming air 2. detecting olfactory stimuli 3. modifying speech vibrations as they pass through the large, hollow resonating chambers

structure and function internal nose

structure: large cavity beyond the nasal vestibule in the anterior aspect of the skull that lies inferior to the nasal bone and superior to the mouth. lined with muscle and mucous membrane. contain paranasal sinuses in the cranial and facial bones function: paranasal sinuses produce mucus and serve as resonating chambers for sound as we speak or sing.

respiratory bronchioles

terminal bronchioles that have subdivided into microscopic branches, as they penetrate more deeply into the lungs, the epithelial lining changes from simple cuboidal to simple squamous

respiratory membrane

the exchange of O2 and CO2 between the air spaces in the lungs and the blood takes place by diffusion across the alveolar and capillary walls

arytenoid cartilage

the most important cartilage because they influence changes in position and tension of the vocal folds. form synovial joints with the cricoid cartialge and have a wide range of mobility

ventilation-perfusion coupling

the perfusion (blood flow) to each area of the lungs matches the extent of ventilation (airflow) to alveoli in that area

carina

the point where the trachea divides into right and left primary bronchi, is formed by a posterior and somewhat inferior projection of the last tracheal cartilage

external nose

the portion of the nose visible on the face and consists of a supporting framework of bone and hyaline cartilage covered with muscle and skin and lined by a mucous membrane.

bronchopulmonary segment

the segment of lung tissue that each tertiary bronchus supplies