Respiratory System & Breathing

gas exchange, thermoregulation, pH homeostasis, sound production, and olfaction (smelling)

functions of the respiratory system

upper respiratory tract

region that begins with the nostril and ends with the larynx

lower respiratory tract

region that begins with the larynx and ends at the alveoli

warm, moisturize, filter, and conduct air

function of upper respiratory tract

vocalization, protection, conduct air, and external respiration

function of lower respiratory tract

right side has 3 lobes and left side has 2 lobes

How many lobes does each side of the lung have?

bronchopulmonary segments

What is the bronchial tree subdivided into based on lobe divisions?

pleura

serous membrane of the respiratory system

surfactant

coats alveoli and makes it easier for them to inflate and deflate

300 million

amount of air sacs

terminal bronchioles

last passageway that lacks any gas exchange potential

respiratory bronchioles

where gas exchange begins

alveolar ducts

direct air into clusters of alveoli

alveolar sacs

clusters of alveoli

external nares → nasal cavity → pharynx → larynx → trachea → primary bronchi → secondary bronchi → tertiary bronchi → bronchioles → terminal bronchioles → respiratory bronchioles → alveolar ducts → alveolar sacs → alveoli

pathway through the respiratory system

changes in thoracic cavity and intrapulmonary pressure

What causes air to move through the lungs?

the longs are in a sealed cavity, so the air moves as a continual column

What does it mean that the respiratory system is a sealed system?

pneumothorax

breaking of the sealed system causing air to enter the chest, which then causes a collapsed lung

inhalation/inspiration

volume increases and pressure inside falls, so air flows in

exhalation/expiration

volume decreases and pressure inside rises, so air flows out

primary inspiratory muscles

muscles that are used all the time to inhale

external intercostals and diaphragm

What specific muscles are always being used to inhale

accessory inspiratory muscles

muscles that are used to help you inhale only when exercising to keep up

no

When at rest, are there any muscles being used to help you exhale?

accessory expiratory muscles

muscles that are used to help you exhale only when exercising to keep up

active (requiring muscle activity)

inhalation is always…

passive (requires no muscle activity)

exhalation is typically…

forced breathing

breathing during exercise is called…