respiratory system

cellular respiration

****cell energy****

metabolic reactions that cells perform to produce the energy needed to live—-oxygen supports aerobic ATP production

cardiovascular system

transports oxygen and carbon dioxide

respiratory system main function

permits intake of oxygen and removes carbon dioxide

expiration

gases exchanged between atmosphere, blood, and cells

• ventilation

• gas exchange

• gas transport

nasal cavity hair

traps big airborne particles

cilia

sweeps mucus and its trapped debris/pathogens toward pharynx

alveolar macrophages

eat small particles that reach lungs

pharynx

muscular tube that allows the passage for air and food

***resonating chamber for speech sounds

***houses tonsils

Larynx

“voice box”

***passage connecting pharynx and trachea——regulates the opening into the lower respiratory system and produces speech sounds

trachea

“windpipe”

airway extends from inferior larynx to right and left main bronchi

*****cartilage rings keep airway open

***epithelium cilia sweep debris away from lungs and towards throat

mucous cells and glands

coat respiratory tract with a sticky mucus to “trap unwanted stuff”

right main bronchi

branches many times after enters lungs at RIGHT hilum

left main bronchi

branches many times after enters lung at LEFT helium

alveoli

tiny air sacs in the lungs where gas exchange occurs

external respiration

the exchange of gases between the lungs and the blood

internal respiration

the exchange of gases between the blood and body tissues

apnea

a temporary cessation of breathing during sleep

lamina propria

the underlying layer of areolar tissue tat supports the respiratory epithelium

epistaxis

a nosebleed, often caused by trauma, drying, infections, allergies, or hypertension

epiglottis

cartilage that forms a lid over the glottis during swallowing

glottis

opening at which inhaled air enters the larynx

phonation

sound production at the larynx

bronchial tree

the branching system of bronchi and bronchioles that conducts air from the trachea into the lungs

alveolar ducts

connects respiratory branchioles to multiple alveoli

pneumonia

an infection or inflammation within the lung that causes fluids to lead into the alveoli, restricting air passage

hilum

the groove that allows passage of the main bronchi, pulmonary vessels, nerves, and lymphatics

bronchial arteries

supply blood to the conducting portions of the respiratory system

upper respiratory

• nose

• nasal cavity

• sinuses

• pharynx

****these structures filter, warm, and moisten air before it enters the lower respiratory system

lower respiratory system

• larynx

• trachea

• bronchi

• lungs

trachea and bronchi

maintain an open airway to the lungs where gas exchange occurs

external nares

two openings that serve as the primary rout for air entering the respiratory system

nasal vestibule

inside external naris———contains coarse hairs that help prevent large airborne materials such as dirt from entering the respiratory system

dorsum nasi

composed of nasal cartilage——external portion of the nose that forms the bridge

spirometer

instrument used to measure respiratory volumes

wet spirometer

***more accurate****

a bell-shaped container inside a chamber filled with water——as you exhale into the mouthpiece, the air displaces water in the container and the container rises and moves —-gauge indicates the volum

dry spirometer

has a turbine that turns as exhaled air passes through it——as turbine moves the needle of the gauge indicates volume of air

vital capacity

the maximum amount of air that can be exhaled from the lungs after a maximum inhalation

***volume averages 4800 mL in males and 3100 mL in females

VC = IRV + TV + ERV

passive process

****expiration/exhalation****———occurs when the muscles just used in inspiration relax and the thoracic wall and elastic lung tissue recoil

active process

***inspiration/inhalation****———requires the contraction of several muscles to change pulmonary volumes and pressures

intrapulmonic pressure

pressure inside the respiratory tract at the level of the alveoli

decrease in thoracic pressure that causes a concurrent expansion of the lungs and a decrease in the pressure of the air in the lungs———causes air to flow into the lungs

contracted diaphragm

lowers and flattens the floor of the thoracic cavity

relaxed diaphragm

dome-shaped

boyle’s law

explains how changing the size of the thoracic cavity creates the pressure gradient necessary for breathing

the pressure of gas in a closed contain is inversely proportional to the volume of the contain——-if the container is made smaller, the gas molecules exert the same amount of force on a smaller surface area and therefore the gas pressure increases

pressure

the amount of force applied to a given surface area

atmosphere pressure

the pressure of the air outside the body——760 mmHg

***for pulmonary ventilation to take place, the pressure in the thoracic cavity must be different from this

average respiratory rate

12 breaths per minute

expiration

***exhalation***

emptying carbon-dioxide-laden air from the lungs and into the atmosphere

***to occur, pressure in thoracic cavity must be higher than atmospheric pressure

inspiration

***inhalation****

the movement of oxygen-rich air into the lungs

to occur, pressure in the thoracic cavity must be lower than atmospheric pressure

pulmonary ventilation

***breathing****

the movement of air into and out of the lungs

fauces

oral cavity opening

oropharynx

extends inferiorly from the soft palate—-connected to the fauces

**8contains lingual tonsils

nasopharynx

superior to the soft palate and serves as a passageway for airflow from the nasal cavity

***lined with pseudostratified ciliated columnar epithelium—-warms, moistens, and clean air

nasal cavity

the airway from the external nares to the superior part of the pharynx

bohr effect

the increased oxygen release by hemoglobin in the presence of increased carbon dioxide levels

lungs

the paired organs of breathing enclosed by the pleural cavities

hypercapnia

high blood carbon dioxide concentrations——commonly results from hypoventilation or inadequate tissue perfusion

bronchodilation

the dilation of the bronchial passages——-can be caused by sympathetic stimulation

cricoid cartilage

a ring-shaped cartilage that forms the inferior margin of the larynx

surfactant

a lipid secretion that coats the alveolar surfaces of the lungs and prevents collapse

soft palate

the fleshy posterior extension of the hard palate——-separates the nasopharynx from the oral cavity

chloride shift

the movement of plasma chloride ions into red blood cells in exchange for biocarbonate ions generated by the intracellular dissociation of carbonic acid

anoxia

inadequate oxygen reaching body tissues

pleura

the serous membrane that lines the pleural cavities (lungs)

Keeps movement smooth and coordinated

inspiratory reserve volume (IRV)

the amount of air that can be forcibly inspired above normal inhalation

**average male is 3300 mL

**average female is 1900 mL

Tidal volume (TV)

the amount of air an individual inspires and exhales during a normal resting breathing rate

***averages 500 mL

expiratory reserve volume (ERV)

the amount of air that can be forcefully exhaled after a normal exhalation

***average is 1000 mL

Type 1 pneumocytes

thin squamous cells forming most of the gas exchange surface

Type 2 pneumocytes

secrete pulmonary surfectant

right lung is____

slightly larger than the left lung and has three lobes

bronchodilation

***smooth muscle regulates bronchiolar diameter

***sympathetic

widens the airway and reduces resistance

bronchoconstriction

**regulated by smooth muscle

****parasympathetic

narrows airway and increases resistance

visceral pleura

covers the lung surface

parietal pleura

lines the inner thoracic wall, mediastinum, and diaphram

pleural cavity

thin potential space between visceral and parietal pleura——→ contains pleural fluid

pleural fluid

reduces friction and helps couple lung movement to chest movement

quiet inhalation

requires muscle contraction

when diaphragm and external intercostal muscles contract, it INCREASES the thoracic cavity volume and DECREASES pressure

quiet exhalation

mainly uses elastic recoil after the inspiratory muscles relax

forced exhalation

recruits muscles such as the abdominal muscles and internal intercostals to push air out more forcefully

alveolar epithelium

***lines exchange surfaces of alveoli

• very delicate—-simple squamous epithelium

• contains scattered, specialized cells throughout alveoli

respiratory defense system includes

• nasal cavity filtration

• mucous cells and glands

• cilia

• alveolar macrophages (last line of defense)

nasal cavity filtration

removes large particles

nasal septum

divides nasal cavity into left and right sides

meatuses (of nasal choanae)

narrow passageways that produce air turbulence to:

• trap particles in mucus

• warm and humidify incoming air

• bring olfactory stimuli to olfactory receptors

bronchial tree

includes trachea, bronchi, and bronchioles

alveolar ventilation

movement of air into and out of alveoli

vestibular folds/ ligaments

inflexible and prevent foreign materials from entering the airway——> also close the glottis during coughing and sneezing

vocal folds/ ligaments

***inferior to vestibular folds

“vocal cords”——> vibrate and produce speech and other sounds

intrinsic muscles of larynx

move the arytenoid cartilage and change the tension on the vocal folds to produce different sounds

c-shaped tracheal cartilages

prevent trachea collapse or overexpansion as pressure change in the respiratory system

coughing reflex

triggered when food particles or liquids manage to touch the surfaces of the vestibular folds or the glottis

internal respiratory exchange

takes place between systemic capillaries and the interstitial fluid that surrounds the cells

respiratory membrane

***very tin

• oxygen and carbon dioxide diffuse quickly because of the large surface area

• consists of the fusion of simple squamous of an alveolus with the endothelium of a pulmonary capillary

hemoglobin carrying capacity

can carry 4 O2 (oxygen) molecules

carbon dioxide is transported_____

in the blood mostly as a bicarbonate ion

conducting zone

series of passageways that carry air to and from the gas-exchange surface

begins at the nasal cavity——> pharynx—→ larynx——> trachea—→ bronchi——> larger bronchioles

respiratory zone

provide a large surface area for gas exchange

****includes the narrowest respiratory bronchioles and their associated alveoli

carbon dioxide transport

****mostly as bicarbonate ions!!!!! (70%)

• 7% dissolves into plasma

• 23% combines with hemoglobin