Gas Exchange

-Allowing oxygen from the air to enter the blood

-&carbon dioxide from the blood to exit into the air

-Breathing (ventilation)

-External respiration

-Internal respiration

-Transport of gases

Traces the path of air from the nose to the lungs

-Nasal hairs, cilia, & mucus

-Inhaled air is warmed by superficial blood vessels lining the airways

-Air is moistened by the mucous membrane

-Clean inhaled air

-Act as defenses against invading organisms

-Mucus contains lysozymes which help kill bacteria

The throat

-connects the nasal & oral cavities to the larynx

-3 parts: nasopharynx, oropharynx, laryngopharynx

-Acts as a passageway for food

-Air passage & food passage cross

Prevents food from entering the air passage (larynx)

The larynx (voicebox) houses the vocal cords

-Air moves up through the cords

-Cords vibrate

-Produces sound

Supplies each lobe of the lung

-3 for right lung

-2 for left lung

-Divide into tertiary bronchi

-Alveolar sacs are made up of simple squamous epithelium, surrounded by blood capillaries

-Site of gas exchange-between air in alveoli & blood in capillaries

Double layered serous membrane

-visceral pleura adheres to the surface of the lung (innermost layer)

-parietal pleura lines the inside of the thoracic cavity

Pressure that forms between the two layers of the pleura

The manner in which air enters & exits the lungs

-Inspiration--> inhale

-Expiration--> exhale

Muscle involved in breathing

-found at the floor of the chest cavity

-contracts during inspiration

-relaxes during expiration

-controlled by phrenic nerve

air mvoed in & out with each breath

-how much in, how much out

-about 500mL

Maximum volume of air moved in & out during a single DEEP breath

-how much we can 'potentially' get in

-2900mL inpiration reserve

-1400mL expiration reserve

Amount of air remaining in lungs after a very deep exhalation

-1000mL

Exchange of gases in the lungs

-between air in the alveoli & blood in the pulmonary capillaries

Oxygen

higher concentration in alveoli

diffuses from alveoli to blood

Carbon Dioxide

higher concentration in blood

diffuses from blood to alveoli

Exchange of gases in the tissues

-between the blood in systemic capillaries & tissue fluids

Oxygen

higher concentration in blood

diffuses from blood to tissue fluid

Carbon Dioxide

higher conc. in tissue fluid

diffuses from tissue fluid to blood

Pigment in RBC's responsible for oxygen transport

Diffusion acts as the primary agent of all gas exchange

-oxygen & carbon dioxide

Emphysema

Lung Cancer