COUGH

Take a deep breath Close glottis Air forced upward Pushes against glottis

forcing air through Triggered by a reflex

SNEEZE

Like a cough Clears upper

respiratory organs; rather than lower organs

Stimulated by an irritant in the nasal lining

Can propel a particle 200 miles per hour!

LAUGHING

Taking breaths & releasing them in short expirations

CRYING

Action similar to laughing

Facial expressions and emotion distinguish the difference!

HICCUPS

Sudden inspiration due to spasm of diaphragm

Air strikes the vocal cords while glottis is closed…creates the “Hiccup” sound

YAWN

Low blood oxygen in the lungs triggers yawning

Therefore, not all the alveoli are vented

This prompts deep breath (in order to vent more alveoli

The Respiratory Center

Groups of neurons in brain stem that control inhalation & exhalation

RHYTHMICITY AREA OF MEDULLA

normal & forceful breathing

PNEUMOTAXIC AREA OF PONS

control breathing rate

Factors that affect breathing:

Chemicals in body fluids

(CO2, H+, blood O2)• Degree to which lung tissue can stretch

(inflation reflex: regulate depth of breathing; prevents over-inflation of lungs)

• Emotional state (fear, pain) can cause HYPERVENTILATION:

abnormally deep & rapid breathing (lowers CO2 levels)

GAS EXHANGE

Occurs in alveoli DIFFUSION through

capillaries If all capillaries in

alveoli were stretched out they would stretch about 620 miles!

GAS TRANSPORT

Oxygen combines to HEMOGLOBIN (the iron portion) & is carried through blood

Less than 2% O2 is dissolved in plasma

GAS EXCHANGE, con’t

70% CO2 is transported by the bicarbonate ion (HCO3)

23% CO2 combines to the protein portion of hemoglobin

7% CO2 is dissolve in plasma