Respiratory system

conducting zone

• conduct air into the lungs

• nose, pharynx, larynx, trachea, bronchi, bronchiole, and terminal bronchioles

• Upper/lower respiratory tract

gas exchange zone

• Cells continually use O2 & release CO2

• what the respiratory system is designed for

• Cardiovascular system transports gases in blood

respiratory system functions

• Pulmonary ventilation: breathing

• Pulmonary gas exchange

• gas transport

• Tissue gas exchange

additional respiratory system functions

• Regulation of blood pH

• Production of chemical mediators: ACE; regulating BP

• Voice production

• Olfaction: smell

• Protection

external nose

• chamber for air inspiration

• Skin, nasal bones, & hyaline cartilage lined with mucous membrane

nasal cavity

• warming, moistening, and filtering incoming air

• receiving olfactory stimuli

• serving as large, hollow resonating chambers to modify speech sounds

pharynx

• throat; passageway for food and inspired air

• resonating chamber for speech production

larynx

• voice box; keeps airway constantly open

• Prevents materials from entering it and lower respiratory tract

• Produces sound for speech

• Protects lower respiratory from microorganisms

trachea

• windpipe; allows air to flow into the lungs

• composed of smooth muscle, dense regular CT and C shaped rings of cartilage

bronchi

airways; directs air into the lungs

lungs

contains air sacs called alveoli and capillaries

nasopharynx

• Upper part of the throat behind the nose

• Passageway for air only

• Contains the openings of auditory (Eustachian) tubes equalizes air pressure

• Contributes to voice resonance/production

oropharynx

• Consists of the back of the throat, tonsils, and posterior tongue

• Allows air, food, and fluid to pass

• Made up of stratified squamous epithelium

laryngopharynx

• Common passageway for food & air; ends at esophagus inferiorly

• stratified squamous epithelium protects the pharynx from abrasion with swallowing

thyroid cartilage

• forms adam’s apple

• Protects the vocal cords, modulation of voice and attachment point for neck muscles

cricoid cartilage

• ring of cartilage encircles the trachea

• Attachment point for muscles/ligaments, supports the connective tissue

epiglottis

• leaf-shaped piece of elastic cartilage

• Freely movable flap during swallowing

• Divert food away from the trachea during swallowing

Pair of arytenoid cartilages

• Muscles movement adjusting for change in sound pitch

• Keep airway open through the larynx

Corniculate cartilage

• Elastic cartilage

• Relaxing and tensing the vocal cords

• Allowing the opening and closing of the glottis (contain the vocal cords

Cuneiform Cartilage

Support epiglottis and vocal cords

Tracheal rings

C-shaped; keep the airway open, prevent trachea from collapsing

cilia of the epithelium

sweep debris away from the lungs and back to the throat to be swallowed

Trachealis muscle

contract which aids in coughing

carina

• prevents choking by coughing

• separates the opening of the right and left primary bronchi

secondary bronchi

• Branches from the primary bronchi

• Smooth muscles and lined with pseudostratified ciliated columnar epithelium

• 2 lobar in left lung, 3 lobar in right lung

Conducting bronchioles

carry air into the alveoli

Terminal bronchioles

No cartilage, smooth muscle layer, lined with ciliated simple cuboidal epithelium

Respiratory bronchioles

Attached to the alveoli, passes air into the alveoli

alveoli

• Site for gas exchange

• Air-filled chambers where the air an the blood come into close contact with each other

• Located at the end of the respiratory bronchioles

Alveolar ducts

Passageway into the deeper portion of the alveoli

Alveolar sacs

• Chambers connected to two or more alveoli

• Located at the end of the alveolar ducts

lungs

• three lobes: Superior, middle and inferior lobes, divided by horizontal and oblique fissures

• two lobes: superior and inferior lobes, divided by the oblique fissure

base

portion of the lungs in contact with the diaphragm

apex (cupula)

portion of the lungs that extends to the clavicle

hilum

indentation in lung, where you find the main bronchi's, BV, nerves and lymphatic vessels

pleura of lungs

• parietal: Membrane surrounding the outside of the lungs

• visceral: Membrane which lines directly the organ (lungs)

• Found within the thoracic cavity

blood supply to the lungs

• Pulmonary circulation

• Oxygenated blood: moves from the lungs (alveoli) to the heart

• Deoxygenated blood: moves from the heart to the lungs

Superficial lymphatic vessels

Drain lymph from the superficial lung tissue and the visceral pleura

Deep lymphatic vessels

Drain lymph from the bronchi and bronchioles

boyle’s law

• volume of a gas varies inversely with pressure, assuming that temperature is constant

• ex. volume of a container increases, the pressure in the container decreases

dalton’s law

• Total atmosphere pressure is the sum of the partial pressure of individual gases

• Each gas in a mixture of gases exerts its own pressure

henry’s law

• amount of dissolved gas in a liquid is proportional to its partial pressure above the liquid

• High concentration to low concentration gradient

• ex. oxygen and carbon dioxide now inside the lungs

Deep Muscles of inspiration

• increase volume of thoracic cavity; expanding lungs

• Diaphragm, Pectoralis minor, Scalene muscle, Sternocleidomastoid muscles

Deep Muscles of expiration

• decrease thoracic volume

• Intercostals ribs, Rectus abdominis, internal oblique, transversus abdominis

tidal volume

500 ml; normal volume of air inspired and expired with each breath (at rest)

inspiratory reserve volume

3000 ml; amount of air that can be inspired forcefully after a normal inspiration

Expiratory reserve volume

1100 ml; amount of air that can be forcefully expired after a normal expiration

Residual volume

1200 ml; volume of air remaining in the respiratory passage and lungs after the most forceful expiration

Inspiratory capacity

tidal volume (inhale) + inspiratory reserve volume

Expiratory capacity

tidal volume (exhale) + expiratory reserve volume

Functional residual capacity

expiratory reserve volume + the residual volume=amount of air remaining in the lungs at the end of normal expiration

Vital capacity

sum of the inspiratory reserve volume + tidal volume + expiratory reserve volume = maximum volume of air a person can expel after maximum inspiration

Total lung capacity

tidal volume + expiratory reserve volume + inspiratory reserve volume + reserve volume

Carbon dioxide out from tissue

1. Carbon dioxide in the tissue diffused into the plasma and into the RBC

2. Outside the RBC: Carbon dioxide reacts with water to form carbonic acid

3. Inside the RBC: Carbon dioxide reacts with water to form carbonic acid, using carbonic anhydrase enzyme and disassociates to HCO3 + H+

4. Carbon dioxide binds to hemoglobin (Hb) and form carbaminohemoglobin (HbCO3)

Oxygen out from RBC into the tissue

• Oxygen with hemoglobin dissociated from each other

• hydrogen ions from carbon dioxide will force oxygen to separate from hemoglobin allowing carbon dioxide to bind to hemoglobin

carbon dioxide out of RBC

1. Outside the RBC: RBC carbon dioxide diffuses out straight from the RBC

2. Outside the RBC: Hydrogen binds to Bicarbonate forming H2CO3) which disassociates into carbon dioxide and water and carbon dioxide diffuses out of the

3. Inside the RBC: Bicarbonate outside the cell diffuses into the RBC and Chloride shift occurs, allowing the bicarbonate ion to diffuse into the RBC and Cl to diffuse out using carbonic anhydrase splitting carbonic acid into water and carbon dioxide causing carbon dioxide to diffuse out of the RBC

4. Hemoglobin with carbon dioxide splits into the hemoglobin and carbon dioxide and carbon dioxide diffuses out

oxygen into RBC in the lungs

1. Oxygen attaches to the free hemoglobin and form hemoglobin oxygen

2. Outside the RBC: Oxygen diffuses into the plasma and into the RBC and bind to hemoglobin

Chemoreceptors

transmits nervous signals to the respiratory center to regulate respiratory activity

Ventral respiratory group

Normal, involuntary rhythm of breaking called eupnea; Mostly expiratory

Dorsal respiratory group

Mainly inspiratory

Pontine respiratory group

Neurons in the pons help control breathing/ventilation rate

aging respiratory system

• tissues & chest wall become more rigid

• Vital capacity decreases to 35% by age 70

• Decrease in macrophage activity

• Diminished ciliary action

• Decrease in blood levels of O2

• age-related susceptibility to pneumonia or bronchitis