Respiratory System Flashcards
cellular respiration happens where?
In mitochondria
food molecules break down in the presence of _
O2
release of energy from the breakdown of food, this makes _
ATP
Human resp. sys. consists of… 6 things
nose, pharynx, larynx, trachea, lungs, bronchi
air moves through… 3 things
nose, pharynx, trachea
_ covers the entrance to the trachea when you swallow
epiglottis
to keep lung tissues healthy, air must be ,, & _.
warmed, moistened, & filtered
large dust particles are ceased by…
nose hairs lining nasal cavity
some cells lining the RS produe a thin layer of…
mucus
moisten the air & traps inhaled particles
mucus
_ sweep the paticles & mucus towards the pharynx
cilia
either swallowed or spit out
cilia
top of trachea
larynx
contains 2 highly elastic folds of tissue known as the vocal chords
larynx
_ pull the vocal cords together
muscles
From the trachea, air flows into 2 large passageways in the chest cavity called _
bronchi
each broncus leads into…
one of the lungs
each bronchus subdivides into …
smaller bronchi
the smaller bronchi lead to even smaller passageways called _
bronchioles
bronchi & bronchioles surrounded by smooth muscle that: 2 things..
helps support them, & enables the ANS (autonomic nervous system) to regulate the size of passageways
the bronchioles continue to subdivide, eventually reach dead ends-millions of tiny air sacs called _
alveoli
each alveolus is surrounded by a network of…
thin-walled capillaries
how many alveoli in each lung?
150 million
O2 dissolves in the moisture & then diffuses across the _ in the blood
capillaries
_ in the bloodstream diffuses in the opposite direction
CO2
Air inhaled contains: _% O2, & _% cO2
21 % O2, .04% CO2
Air exhaled contains: _% O2, & _% cO2
less than 15% O2, 4 % CO2
no _ connected to the lungs
muscles
force that drives air into lungs comes from:
ordinary air pressure
during inhalation, rib cage _, the diaphragm _, increasing the size of the chest cavity
rib cage rises, diaphragm contracts
inhaling causes the pressure inside the lung to _, and air enters
decrease
When the rib cage lowers and the diaphragm muscles relax: the pressure in the chest cavity becomes greater than _
atmospheric pressure
part of the brain that controls breathing:
medulla oblongata
cell in its breathing center monitor the amount of _ in the blood
CO2
the higher the CO2 level, the stronger the…
impulses
as the _ level rises, automatic nerve impulses from the breathing center cause the diaphragm to contract, bringing air into the lungs
CO2
