Lungs Quiz phys

Ventilation

Air exchange between environment and

lung sacs

• O2 and CO2 exchange between alveoli

and blood

• O2 and CO2 exchange between blood

and tissues

If there is too much CO2 in alveolus, too little O2 for blood to pick up,

causes

Vasoconstriction to reduce blood flow

•Bronchodilation to increase airflow

If there is too little CO2 in alveolus, too much O2 for blood to pick it all

up, causes:

Vasodilation to increase blood flow

Bronchoconstriction to decrease airflow

Control of Respiration feedback loop

Chemical formula

2 types of Chemoreceptors

peripheral

central

peripheral Chemoreceptors

Located in arteries (carotid, aorta)

• Detect level of CO2 in blood as carbonic acid (H+ ions)

Central chemoreceptors

• Located in medulla

• Detects level of CO2 in blood

-Only CO2 can pass blood-brain barrier

2 parts of the respiratory center

Medullary respiratory center

Pontine respiratory group

Medullary respiratory center

Stimulates diaphragm and

intercostal/abdominal muscles for

breathing

Pontine respiratory group

• Involved with switching between

inspiration and expiration

• Affects rate and tidal volume

Tidal volume

the amount of air that moves in or out of the lungs with each normal, quiet breath

Dead Space

• Volume of air inhaled that does not

participate in gas exchange

• Air in conducting airways (trachea, bronchi,

etc)

• Air in not properly perfused alveol

Dead space picture

Emphysema causes shortness of breath because

long-term damage destroys the thin walls of the lungs' tiny air sacs (alveoli), making them lose their stretchiness and rupture.

significant loss in elastic recoil

vital capaity

the maximum amount of air a person can exhale after taking a deepest possible inhalation

negative feedback loop

Alveolar sacs

clusters of tiny, cup-shaped air spaces located at the very end of the respiratory tree in the lungs

surfacant

aqueous film that cover alveolar sacs to make sure they dont stick together.

atelactasis

the partial or complete collapse of a lung or a lobe of a lung

2 phases of ventilation

inspiration

expiration

inspirations occurs as the

external intercostal muscles and diaphragm contract