Anatomy

Parts of the pharynx

nasopharynx, oropharynx, and nasopharynx

nasopharynx

receives air from the nasal cavity via internal nares

Oropharynx

receives food from the mouth and air

laryngopharynx

both food and air travel through; food then routed into the esophagus

what are the tonsils founds in the pharynx and their locations

Pharyngeal- nasopharynx

Palatine-oropharynx at the end of soft palate

lingual- base of tongue

what are the pharynhotympanic tubes and why are they clinically reelvant

they drain the middle ear into the nasopharynx; their mucoase are continuous, so throat infections can lead to ear infections

function for the pleura

produce pleural fluid; slippery serous secretion that let the lungs glide smoothly during breathing and keeping contact with the thoracic wall

visceral pleura

covers the outer surface of each lung directly

parietal pleura

lines the walls of the thoracic cavity

Pleural space

not a true space, the region between visceral and parietal pleura

The glottis

the slit-like passageway between the vocal folds (true vocal cords) through which air passes

what triggers the cough reflex, and when does it not work

when anything other than air enters the larynx, does not work on a unconscious person

Function of the pulmonary capillary in gas exchange

surrounds alveoli; one cell thick, allowing O2 to diffuse into the blood and Co2 to dissuse out into the blood

Function of the red blood cell in gas transport

carries hemoglobin; picks up O2 at the lungs and delivers it to tissue; intimates conversion of CO2 to bicarbonate ion for transport to plasma

Function for hemoglpbin in O2 transport

protein inside red blood cell that binds O2 to form oxyhemoglobin; released O2 at tissue capillaries where O2 concentration is low

what is the order of divisions from trachea to alveoli

trachea- primary main bronchi- secondary bronchi-tertiary bronchi-bronchioles-alveoli

where do the bronchioles differ from the bronchi

bronchioles lack cartilage; only the smallest passages have cartilage

what type of cells make up the alveolar walls and what is their function

Simple squamous epithelial cells- one cells thick; their extreme thinness allows rapid diffusion of O2 into the blood and CO2 out

What are alveolar pores and why are they important

tinny connections between neighboring alveoli that provide alternate air routes if bronchiole become clogged with mucus

How does the trachea stay open (patent)

c-shapes rings of hyaline cartilage reinforce the walls, prevent collapse during pressure changes in breathing

C-shapes cartilage rings

allows esophagus to expands into that space swallowing food

How do the bronchi stay patent

supported by rings/plates of hyaline cartilage; prevent collapse in air respiration

what is the phrenic nerve and what does it do

cervical nerve that carries motor signals from the brain to the diaphragm, contracting during inspiration

what nerve controls the external intercostal muscles during breathing

intercostal nerves signal external intercostals to contract, lifting the rib cage during inspiration

how many lobes does the right lung have and what are they

superior, middle, and inferior- apex, horizontal fissure, and oblique fissure

How many lobes does the left lung have and what are they

superior and inferior- oblique and cardiac notch

what structures make up the respiratory zone

bronchioles, alveolar ducts, and alveolar sacs- all structural where actual gas exchange occurs

what structures make up the conducting zone

all passages that carry air to the gas exchange sites but do not exchange gases; nose pharynx, larynx, trachea, bronchi, bronchioless, terminal bronchioles

four steps of repiration

1. Pulmonary ventilation

2. external repsiration

3. transportation

4. internal repsiration

Pulmonary ventilation

breathing

External repsiration (location and function)

alveoil/pulmonary capillaries; exchange of gases (\(O_{2}\) and \(CO_{2}\)) between the inhaled air in the lung's alveoli and the blood within pulmonary capillaries.

Respiratory gas transport (location and function)

Bloodstream O2 and CO2 are carried between lungs and body tissue cells via the cardiovascular system

Internal repsiration (location and function)

systemic capillaries/tissue cells; to deliver oxygen to tissues for energy production and remove metabolic carbon dioxide waste

HbO2 and how is it formed

O2 binds to hemoglobin inside red blood cells; formed when O2 diffuses into the blood at the alevoil and attaches the hemoglobin

how is CO2 transported in the blood

70% as bicarbonate ion dissolves in plasma, 20-30% bound to hemoglobin inside red blood cells

what is HCO3 (bicarbonate ion) and how does it form

CO2 enters red blood cells- combines with H2O- forms carboncin acid (h2Co3)- splits into Hco3+H; Hco3 diffuses into plasma for transport

what is H2CO3 (carbonic acid) and its role

intermediate molecule- Co2+h2O-H2CO3 breaks down to Hco3 + H at tissues, reverses at lungs to release co2

What is carbonic anhydrase

Enzyme inside red blood cells that rapidly speeds up conversions of carbon dixoide and water into carbonic acid accerlating co2 transport

How does boyle’s law applies to breathing

volume changes lead to pressure changes, which lead to gas flow equalize pressure

What happens to volume and pressure during inspiration

increased volume leads to a decrease in intrapulmonary (alveolar) pressure below atmospheric pressure

what happens to volume and pressure during expiration

lung volume decreases and lung pressure increases

2 main muscles of inspiration

Diagprham and external intercostals

Whats happens to diaphragm during inspiration vs expiration

Inspiration- diagrpagm contracts and flattens moving area down, thorax gets taller

Expiration- diagrpagm relaxes, thorax shrinks

Insipration active or passive

active-requires muscle contractions to increase thoracic volume

expiration active or passive

muscles relax-=passive

Tidal volume

the amount of air inhaled and exhaled in one normal breathe- 500ml

residual volume

air remaining in the lungs after a maximal exhalation

What Is intrapulomonary volume

the total volume within the lungs on a normal (resting) basis

Whats is total lung capacity

maxinum volume the lings can hold after a maximal inhalation- 6 L in a healthy adult

what is inspiratory reserve volume

extra air that can be inhaled beyond a normal tidal breath (above tidal volume)

what is expiratory reserve volume

extra air that can be forcibly exhaled beyond normal tidal exhalation

what is asthma

narrowed by spasm of the bronchioles, air trapped in alveoli

what is chronic bronchitis

bronchioles filled with excess mucus

what is pneumonia

bronchioles and alveoli filled with fluid, blocking gas exchange

Cystic fibrosis

abnormally thick, sticky mucus fill the lungs and airway

what is pleurisy

inflammation of the pleural membranes

Hypoxia

inadequate O2 delivery to body tissues

Eupnea

Normal, effortless breathing rate 12-15 respirations per minute

Hypernea

increased breathing rate and depth during execise

Dyspnea

labored or difficult breathing

4 factors that influence respiratory rate and depth

Phsycial, conscious, emtional, chemical

what brain regions control breathing rhythm

meduall oblongata sets basic rhythm, pons- smooths and adjusts the rhythm

what is the most powerful chemical stimulus for breathing

Rising CO2, chemoreceptors detect this and signals the medulla to increase rate and depth of breathing