lab practical 2: respiratory system

what are the structures of the upper division

external nose, nasal cavity, paranasal sinus, pharynx

what are the structures in the lower division

larynx, trachea, bronchi, lungs, bronchioles, alveolar ducts, alveoli

what are the functions of the nasal cavity

filters, warms, and moistens incoming air

what structure is the resonating chamber for voice

nasal cavity

what are the included structures of the nasal cavity

external nares (nostrils)

function of the pharynx

connects nasal and oral cavities to larynx and esophagus

regions of the pharynx

nasopharynx, oropharynx, laryngopharynx

nasopharynx

most superior region, only involved in respiration

oropharynx

middle region, from soft palate to epiglottis, involved in respiratory, and digestive functions

laryngopharynx

most inferior region, from epiglottis to larynx, involved in respiratory and digestive functions

function of larynx

prevents food/fluid from entering lungs, permits the passage of air and produces sound

what is the larynx made of

cartilaginous and membranous structures

what are the cartilages of the larynx

thyroid cartilage, cricoid cartilage, arytenoid cartilage, epiglottis

what type of cartilage is the thyroid cartilage

hyaline

what type of cartilage is the cricoid cartilage

hyaline

what type of cartilage is the arytenoid cartilage

hyaline

what type of cartilage is the epiglottis

elastic

thyroid cartilage

forms the framework of the larynx, contains laryngeal prominence (adams apple)

laryngeal prominence

adams apple

cricoid cartilage

attaches the larynx to the trachea

arytenoid cartilage

anchors vocal cords

epiglottis

closes the opening to the trachea during swallowing

function of trachea

connects larynx to bronchi

what are the trachea walls reinforced with

C rings of hyaline cartilage

benefits of the C rings of the trachea

allows expansion during swallowing, provides structure to maintain an open airway

epithelium trachea is lined with

pseudostratified ciliated columnar epithelium

function of goblet cells in trachea

produce mucus

function of cilia in trachea

moves mucus away from lungs to throat

bronchi

a series of branching respiratory tubes

trachea divides into

right and left primary bronchi

each bronchus divides into

secondary, tertiary, etc

terminal bronchioles divide into

respiratory bronchioles

respiratory bronchial wall subdivide into

alveola ducts terminating in alveolar sacs

alveolar ducts

divide from respiratory bronchioles

alveolar sacs

clusters of alveoli

alveoli

balloon-like pockets at the end of alveolar ducts

how does gas exchange occur

at alveoli by simple diffusion

what epithelium is alveoli composted of

single layer of simple squamous epithelium

what forms the respiratory membrane

fused basement membranes of alveoli and capillary walls

respiratory membrane

blood air barrier

lungs

soft spongy organs made of respiratory passageways

what tissue are lungs made of

elastic CT

importance of elastic CT in lungs

allows for expansion and contraction

where are lungs located

fills the entire thoracic cavity except for the mediastinum

cardiac notch

concavity of left lung that provides space for the heart

how are the lungs divided

by a fissure

how many lobes does each lung have

left has 2 right has 3

pleurae of the lungs

double layered serous membranes surround each lung

partial pleura

outer layer, attaches to thoracic walls and diaphragm

visceral pleura

inner layer, covering the external surface of the lung

external respiration

gas exchange between air and blood in the lungs

what circulatory system is involved during external respiration

pulmonary circulation

internal respiration

gas exchange between blood and tissues

what circulatory system is involved during internal respiration

systemic circulation

inspiration

air moving into the lungs

explain the physiology of inspiration

Inspiratory muscles contract, the thoracic cavity increases in size, Intrapulmonary volume increases, and intrapulmonary pressure decreases, Air flows to area of lowest pressure (into lungs)

expiration

air moves out of the lungs

explain the physiology of expiration

Inspiratory muscles relax, Thoracic cavity decreases in size, Intrapulmonary volume decreases intrapulmonary pressure increases, Air flows to area of lowest pressure (out of lungs)

tidal volume TV

amount of air inhaled or exhaled with each breath under resting condition

inspiratory reserve volume IRV

Amount of air that can be forcefully inhaled after a normal TV inspiration 

Expiratory Reserve Volume (ERV)

Amount of air that can be forcefully exhaled after a normal tidal volume expiration 

Residual volume (RV)

Amount of air remaining in the lungs after a forced expiration

Total Lung Capacity (TLC)

Max. amount go air contained in the lungs after a max. Inspiratory effort

calculate TLC

TLC= TV + IRV + ERV + RV 

Vital Capacity (VC)

Max. Amount go air that can be expired after a max. Inspiratory effort

Calculate Vital Capacity (VC)

VC= TV + IRV + ERV

Inspiratory Capacity (IC)

Max. amount of air that can be inspired after a normal tidal volume expiration

calculate Inspiratory Capacity (IC)

IC= TV + IRV

Functional residual capacity (FRC)

Volume of air remaining in th lungs after a normal tidal volume expiration

calculate Functional residual capacity (FRC)

FRC= ERV+ RV

Bronchial sounds

produced by air rushing through the large respiratory passageways (trachea and bronchi)

Vesicular breathing sounds

results from air filling the alveolar sacs

how can respiratory sounds be ausculated

using a stethoscope

what can cause abnormal respiratory sounds

diseased tissues, mucus, pus

respiratory sound: rales

rasping sound

respiratory sound: wheezing

whistling sound

obstructive respiratory disease

increases resistance in the airways

affect on lung capacity: obstructive respiratory disease

Normal vital capacity, but decreased rate of air flow due to bronchoconstriction

examples of obstructive respiratory disease

asthma, chronic bronchitis

restrictive respiratory disease

lung capacity declines 

affect on lung capacity: restrictive respiratory disease

vital capacity decrease

examples of restrictive respiratory disease

polio, TB

Forced vital capacity (FVC)

volume of air expelled when subject takes deepest possible breath and then exhales forcefully and rapidly

how is FVC affected in restrictive respiratory disease

FVC will be reduced

Forced expiratory volume (FEV_T)

Looks at the percentage of the vital capacity that is exhaled during specific time intervals (T)

FEV₁

the amount exhaled during the first second of the test

how much FVC can healthy individuals expire

75-85%

How is FEVt affected in obstructive respiratory disease

FEV will reduce

what controls respiratory rhythm and rate

neural centers in the medulla and the pons

normal respiration rate

12-18 respirations/min

what modifys the rate and depth of respiration

physical phenomena and chemical factorsw

what are the physical phenomena that modify the rate and depth of respiration

yawning, talking, coughing, exercise

chemical factors that modify rate and depth of respiration

concentration of O2 and CO2 in blood, fluctuations in pH

Atrial blood pH is regulated by

the carbonic acid-bicarbonate buffer system

Chloride shift

to balance the negative charge of HCO3- leaving the erythrocytes, Cl- is drawn from plasma into erythrocytes

How is CO2 transported into the blood

as bicarbonate (HCO₃⁻)

If pH decreases (Increases in H+)

H+ combines bicarbonate ion to form carbonic acid—a weak acid, This removes free H+ from the blood, buffering against decreases in pH

If pH increases (decrease H+)

carbonic acid dissociates into bicarbonate ions— a weak base , This releases free H+ into the blood, buffering against increases in pH

Hyperventilation

fast, deep breathing

hyperventilation leads to

decrease carbonic acid, less h+, high ph