Respiratory System

Question 1

Functions of the Respiratory System

Answer 1

provide oxygen for cells and remove the waste product carbon dioxide from the body

(or pick up oxygen from the air we inhale and release carbon dioxide into the air we exhale)

Question 2

Parts of the respiratory system

Answer 2

nasal cavity, pharynx, epiglottis, larynx, trachea, bronchi, bronchioles, alveoli, diaphragm, lungs

Question 3

nasal cavity

Answer 3

warms and moistens air; filters out dust and particles

Question 4

pharynx

Answer 4

connects respiratory and digestive systems

Question 5

trachea

Answer 5

the windpipe; contains cilia which lines the trachea and filters air

Question 6

How does cilia filter air?

Answer 6

sweeps mucus and trapped particles away from the lungs and toward the pharynx to be swallowed or spat out

Question 7

bronchi

Answer 7

large tubes in the chest cavity that branches off to one lung each

(singular is bronchus)

Question 8

bronchioles

Answer 8

a division of bronchi that are even smaller passage ways

(singular is bronchiole)

Question 9

alveoli

Answer 9

tiny air sacs at the end of bronchioles where gas exchange occurs

Question 10

What controls the contraction and relaxation of bronchi and bronchioles?

Answer 10

autonomic nervous system controls (brain stem), smooth muscles

Question 11

Path of air in

Answer 11

nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles, alveoli

Question 12

Path of air out

Answer 12

alveoli, bronchioles, bronchi, trachea, larynx, pharynx, nasal cavity

Question 13

How is gas exchanged with the circulatory system?

Answer 13

1. air enters the alveoli
2. blood full of carbon dioxide in capillaries near the alveoli flow through
3. both oxygen and carbon dioxide diffuse from high to low (so oxygen diffuses out of blood and binds to hemoglobin, and CO2 diffuses into the alveoli)
4. blood now filled with oxygen (not entirely) flows back into the heart
   and air from alveoli (now filled with carbon dioxide) gets exhaled

Question 14

What do the mechanics of breathing involve?

Answer 14

rib cage, diaphragm, differences in air pressure

Question 15

Mechanics of inhalation

Answer 15

• muscles in between ribs contract (raises rib cage)
• diaphragm contracts (flattens)
• chest capacity increases
• internal air pressure decreases
• higher air pressure outside than inside

Question 16

What does the rib cage do during inhalation?

Answer 16

muscles in between contract, raising the rib cage

Question 17

What does the diaphragm do during inhalation?

Answer 17

contracts, flattens the diaphragm

Question 18

How is the air pressure inside of the body compared to the outside during inhalation?

Answer 18

internal air pressure is lower
external air pressure is higher

Question 19

How does having a lower air pressure inside help inhalation?

Answer 19

creates a partial vacumn

Question 20

Mechanics of Exhalation

Answer 20

• muscles in between ribs relax (ribcage lowers)
• diaphragm relaxes (moves up)
• internal chest capacity decreases
• internal air pressure increases
• higher air pressure inside than outside
• air flows out

Question 21

What does the rib cage do during exhalation?

Answer 21

relaxes, goes down and inward

Question 22

What does the diaphragm do during exhalation?

Answer 22

relaxes, moves up

Question 23

How is the air pressure inside of the body compared to the outside during exhalation?

Answer 23

internal air pressure is higher
external air pressure is lower

Question 24

What is the regulation of breathing controlled by?

Answer 24

medulla oblongata (part of brain stem)

Question 25

What causes the rate of breathing to increase?

Answer 25

more CO2

Question 26

How does the medulla oblongata help maintain homeostasis?

Answer 26

regulates carbon dioxide levels and ensures there is not too mcuh

Question 27

How does the medulla oblongata regulate carbon dioxide levels?

Answer 27

CO2 lowers blood pH slightly (creates carbonic acid)
sends impulses to muscles in between ribs and diaphragm to contract to get rid of the CO2