Chapter 8

Question 1

Respiration is the process of supplying the body
with O2 and removing CO2.
* It has three basic steps:
1. Pulmonary ventilation or breathing
2. X (pulmonary) respiration
3. Internal (tissue) respiration

Answer 1

External

Question 2

Pulmonary ventilation or breathing: is the
inhalation (inflow) and exhalation (outflow) of air
and involves the exchange of air between the
atmosphere and the X. Inhalation
permits O2 to enter the lungs and exhalation
permits CO2 to leave the lungs.

Answer 2

alveoli of the lungs

Question 3

2. External (pulmonary) respiration: is the exchange of gases between X and the
   X across the
   respiratory membrane. In this process, X gains O2 and loses CO2.

Answer 3

the alveoli of the lungs and the blood in pulmonary capillaries
pulmonary capillary blood

Question 4

3. Internal (tissue) respiration: is the exchange of
   gases between X and
   X. In this step the blood loses O2 and
   gains CO2. Within cells, the metabolic reactions
   that consume O2 and give off CO2 during the
   production of ATP are termed cellular respiration.

Answer 4

blood in systemic capillaries and tissue cells

Question 5

The respiratory system consists of the nose, …. (throat), ….. (voice
box), trachea (windpipe), bronchi, and lungs.

Answer 5

pharynx
larynx

Question 6

Structurally, the respiratory system consists of two parts:

Answer 6

upper and lower

The upper respiratory system includes the nose, nasal cavity, pharynx, and
associated structures;

(2) The lower respiratory system includes the larynx, trachea, bronchi, and lungs.

Question 7

Functionally, the respiratory system also consists of two parts (or ‘zones’):

(1) The X zone: interconnecting cavities and tubes (outside and within the
lungs) that filter, warm, and moisten air and conduct it into the lungs. These include
the nose, nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles, and terminal
bronchioles.

(2) The X zone: tubes and tissues within the lungs where gas exchange occurs.
These include the respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli.

Answer 7

conducting
respiratory

Question 8

Functions of the respiratory system:

1. Provides for gas exchange: intake of O2 for delivery to body cells and removal of CO2
   produced by body cells.
2. Helps regulate X (Chapter 6).
3. Contains receptors for sense of smell, filters inspired air, produces vocal sounds
   (phonation), and excretes small amounts of water and heat.

Answer 8

blood pH

Question 9

In pulmonary ventilation, air flows between the atmosphere and the alveoli of the
lungs because of X differences created by contraction and
relaxation of respiratory muscles.

Answer 9

alternating pressure
The air flows from HIGHER to LOWER pressure.

Question 10

The rate of airflow and the
amount of effort needed
for breathing are also
influenced by:

1. alveolar surface tension
2. compliance of the lungs
3. X

Answer 10

airway resistance

Question 11

Boyle’s law: the pressure of a gas in a closed container is inversely proportional to
the X of the container

Answer 11

volume

Question 12

For air to flow into the lungs, the pressure inside the alveoli must become higher/lower than the atmospheric pressure.

Answer 12

lower

Question 13

And, according to Boyle’s law, for the pressure of the gas (air inside the lungs)
to decrease, the volume of the container (lungs) must increase. how?

1. Contraction of
2. Contraction of

Answer 13

diaphragm and external intercostals (=muscles)

Question 14

Because both, normal quiet inhalation
and inhalation during exercise or
forced breathing, involve muscular
contraction, the process of inhalation
is said to be active.

true/false

Answer 14

true

Question 15

Normal exhalation during quiet breathing, unlike inhalation, is a passive process
because no muscular contractions are involved.

true/false

Answer 15

true

Question 16

1. lung volumes: can be measured directly by use of a spirometer
2. lungs capacities:X

Answer 16

are combinations of different lung volumes

Question 17

The apparatus used to measure volumes
and capacities is called a spirometer or
respirometer.
* The record is called a spiroX

Answer 17

gram.

Question 18

Tidal volume (VT): the volume of X

Answer 18

one breath

Question 19

Respiratory dead space (DS): portion of the tidal volume that X

Answer 19

remains in the conducting
airways does not take part in gas exchange

Question 20

• Effective tidal volume (ETV): volume of air actually X

Answer 20

reaching the alveoli in each
inspiration:

Question 21

Respiratory Rate (RR): x

Answer 21

Number of breaths per minute

Question 22

Minute Ventilation (MV): x

Answer 22

the total volume of air inhaled and exhaled each minute

Question 23

The alveolar ventilation (AV): the volume of air per minute that actually reaches x

Answer 23

the
respiratory zone

Question 24

Inspiratory Reserve Volume (IRV): Maximum volume of air taken in a forceful
inhalation (except the tidal volume).

• Expiratory Reserve Volume (ERV): Maximum volume of air that exits the lungs in
  a forceful exhalation (except the tidal volume).
• Forced Expiratory Volume in 1 second (FEV1): the volume of air that can be
  exhaled from the lungs in 1 second with maximal effort following x

Answer 24

a maximal
inhalation.

SEE P 28

Question 25

What volume cannot be measured by spirometry?

Answer 25

Residual Volume: Volume of air remaining in the lungs at the end of a maximum
exhalation unable to be released from the lungs

Question 26

Inspiratory capacity (IC) is the sum of tidal volume and inspiratory reserve volume.
* Functional residual capacity (FRC) is the sum of residual volume and expiratory reserve
volume.
* Vital capacity (VC) is the sum of inspiratory reserve volume, tidal volume, and expiratory
reserve volume.
* Total lung capacity (TLC) is the sum of vital capacity and residual volume.

Answer 26

ok

Question 26

If the thoracic cavity is opened, the intrapleural pressure rises to equal the
atmospheric pressure and forces out some of the residual volume. The air
remaining is called the minimal volume. Should the volume of the lungs fall
below this value, the lungs will X

Answer 26

collapse
(minimal volume can not be measured by spirometry).

Question 27

Each lung is enclosed and protected
by a double-layered serous
membrane called the pleural
membrane.

• Parietal pleura vs visceral pleura:

which is it?

• superficial
  layer, lines the wall of the
  thoracic cavity/deep layer
  covers the lungs
• Visceral pleura: deep layer,
  covers the lungs.

Answer 27

parietal = superficial
visceral = deep

Question 28

The air passes through the airway branching: starting from the trachea, put in right order:

segmental bronchi
right and left main bronchi
bronchioles
lobar bronchi
terminal bronchioles.

Answer 28

right and left main bronchi
lobar bronchi
segmental bronchi
bronchioles
terminal bronchioles.

Question 29

The portion of lung tissue that each segmental bronchus supplies is called a
bronchopulmonary segment. they each have lobules, which contain a lymphatic vessel, an X, a venule,
and a branch from a terminal
bronchiole.

Answer 29

arteriole

Question 30

Terminal bronchioles and lobule
subdivide into microscopic branches
called X. They also
have alveolibudding from their walls

• X in turn
  subdivide into several alveolar ducts.
• The terminal dilation of an alveolar duct
  is called an alveolar sac.
• Each alveolar sac is composed of
  outpouchings called alveoli.

Answer 30

respiratory bronchioles

Question 31

• The wall of each alveolus consists of:

1. Epithelial cells type I: sites of X
2. Epithelial cells type II: secrete
   alveolar fluid: keeps the surface
   moist and contains surfactant
   (lowers the surface tension of
   alveolar fluid, which reduces the
   tendency of alveoli to collapse).
3. Macrophages (dust cells):
   phagocytes that remove fine dust
   particles and other debris.

Answer 31

gas
exchange.

Question 32

Exchange of gases takes place in the respiratory membrane: a very thin membrane (<0,5
μm) which consists of four layers (from the alveolar air space to blood plasma):

• Epithelial basement membrane
  underlying the alveolar wall.
• Alveolar wall: type I and type II
  alveolar cells and associated alveolar
  macrophages.
• Capillary endothelium.
• Capillary basement membrane: often
  fused to the epithelial basement
  membrane.

put in right order

Answer 32

1. Alveolar wall: type I and type II
   alveolar cells and associated alveolar
   macrophages.
2. Epithelial basement membrane
   underlying the alveolar wall.
3. Capillary basement membrane: often
   fused to the epithelial basement
   membrane.
4. Capillary endothelium.

Question 33

The exchange of O2 and CO2 takes place by
active diffusion across the respiratory
membrane.

true/false

Answer 33

false: passive

Question 34

Passive diffusion is governed by the
behavior of gases as described by two
gas laws:
1. Dalton’s law: important for
understanding how gases move
down their pressure gradients by
diffusion
2. Henry’s law: helps explain how
the solubility of gas relates to diffusion

Answer 34

ok

Question 35

External respiration or pulmonary
gas exchange is the diffusion of O2
from air in the alveoli of the lungs to
blood in pulmonary capillaries and
the diffusion of CO2 in the opposite
direction.

• It converts deoxygenated blood
  coming from the right side of the heart into
  oxygenated blood that returns to the left side of
  the heart.
• Although this process is commonly
  called an “exchange” of gases, each
  gas diffuses independently from the
  area where its partial pressure is
  higher to the area where its partial
  pressure is lower.

Answer 35

ok

Question 36

Internal respiration or systemic
gas exchange is the exchange of
O2 and CO2 between X and X.
* As O2 leaves the bloodstream,
oxygenated blood is converted
into deoxygenated blood.
* Unlike external respiration, which
occurs only in the lungs, internal
respiration occurs in tissues
throughout the body

Answer 36

systemic
capillaries and tissue cells

Question 37

The size of the thorax is altered by
the action of the breathing muscles,
which contract as a result of nerve
impulses transmitted from centers in
the brain and relax in the absence of
nerve impulses.

the region taking care of this is called the X center

Answer 37

respiratory

Question 38

Activity of the respiratory center can be modified in response to:

1. Inputs from other brain regions:
   cerebral cortex
2. X
3. Other factors

Answer 38

receptors

Question 39

Chemoreceptors in two locations of the respiratory
system monitor levels of CO2, H+, and O2 and provide
input to the respiratory center:

1. X chemoreceptors:
2. Peripheral chemoreceptors:

Answer 39

Central

Question 40

In/decreased PCO2, in/decreased pH (in/decreased H+), or in/decreased PO2, input from the central and
peripheral chemoreceptors causes the respiratory center to become highly active.

Answer 40

Increased PCO2, decreased pH (increased H+), or decreased PO2

Question 41

As soon as you start exercising, your rate and depth of breathing increase, even before changes
in PO2, PCO2, or H+ level occur.

• The main stimulus for
  these quick changes in
  respiratory effort is input
  from Xceptors,
  which monitor movement
  of joints and muscles.
• Nerve impulses from the
  proprioceptors stimulate
  the respiratory center of
  the medulla.
• Upper motor neurons that
  originate in the primary
  motor cortex also feed
  excitatory impulses into
  the respiratory center.

Answer 41

proprio

Question 42

Stretch-sensitive receptors (baroreceptors) are located in the walls of bronchi and bronchioles.

• When stretched during overinflation of the lungs, nerve impulses are sent along the vagus (X)
  nerves to the respiratory center. resp center is inhibited -> inflation reflex

Answer 42

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