Respiration

Question 1

where does respiration occur

Answer 1

in the lungs

maintains PH, oxygen, and CO2

Question 2

Animals must exchange the respiratory gases

Answer 2

O2 and CO2 via passive diffusion

Question 3

Gas exchange systems are made up of:

Answer 3

Specialized surfaces where gas can move
between the body and the environment
• Mechanisms that ventilate the
environmental side and perfuse the
internal side

Faster diffusion–>faster exchange–> possibly better metabolism

Question 4

Partial pressure

Answer 4

concentration of a gas in a mixture of gasses

Question 5

Fick’s law of diffusion

Answer 5

applies to all gas exchange of systems
Q=DA(P1-P2)/L)

Q= rate of diffusion
D= diffusion coefficient
A=area across which gases diffuse

P1 and P2= partial pressures of gas at two locations

L=distance btw the locations
(P1-P2)/L: partial pressure gradient

surface area (A) x concentration difference (P1-P2) x membrane permeability (D)/ membrane thickness (L)

Question 6

what plays a role in membrane permeability

Answer 6

lipid solubility and molecular size

Question 7

increase in surface area (A)

Answer 7

faster rate of diffusion

Question 8

increasing concentration difference (P1-P2)

Answer 8

faster rate of diffusion

Question 9

increasing permeability (D)

Answer 9

faster rate of diffusion

Question 10

increased membrane thickness

Answer 10

slower rate of diffusion

Question 11

adaptations to maximize respiratory gas exchange

Answer 11

increase surface area (A)

maximize partial pressure gradients (p1-p2)
(decrease partial pressure in tissues)

minimize diffusion path length (L)
thinner tissues in gills and lungs

maximize diffusion that takes place into and in aqueous medium
circulating blood and active moving of air and water

Question 12

insects have

Answer 12

spiracles where air diffuses into the body

Question 13

fish have

Answer 13

gill slits that increase surface area with thin layers

Question 14

ventilation

Answer 14

breathing

Question 15

tidal volume

Answer 15

normal amount of air exchanged breathing at rest

Question 16

expiratory reserve

Answer 16

volume of additional air that can be forcefully exhaled

Question 17

inspiratory reserve

Answer 17

• additional capacity of the lungs enables deepest breath

Question 18

residual volume

Answer 18

amount of air left in lungs after maximum exhalation

AIR CAN’T BE EXPELLED FROM LUNGS

will NEVER GO TO 0

Question 19

Vital Capacity

Answer 19

(VC)= TV+ IRV+ERV

Question 20

Functional residual volume (FRV)

Answer 20

ERV+RV

Question 21

Residual volume contributes

Answer 21

to FRV and to dilution of O2 in inhaled air

Question 22

thoracic cavity

Answer 22

where human lungs are suspended inside this

Question 23

diaphragm

Answer 23

a sheet of muscle at the

bottom of the cavity.

Question 24

pleural membrane

Answer 24

covers each lung and
lines the thoracic cavity.

The pleural space contains fluid to help the membranes
slide past each other during breathing.

Question 25

negative pressure

Answer 25

created in the pleural
space when the
volume of the thoracic
cavity increases.

slight negative
pressure keeps
alveoli inflated, even
in between breaths.

Question 26

surfactant

Answer 26

reduces the surface tension of a liquid.

gives the surface of a liquid
the properties of an elastic membrane; results from
attraction between water molecules

makes it easier to breathe

allows the inflation of the lungs

one of the last things to develop in newborns

Question 27

fluid covering inside of the alveoli

Answer 27

has reduced
surface tension that makes the lungs elastic.

Lung surfactant is released by cells in the alveoli when
they are stretched.

It is critical for reducing the work needed to inflate the
lungs.

Premature babies may not have developed the ability to make lung
surfactant; without it, they have great difficulty breathing and may die
from exhaustion and lack of O2.

Treatments include respirators,
hormones to speed lung development, and aerosol surfactants.
2

Question 28

purpose

Answer 28

All this gas exchange occur in the alveoli
o VERY VERY thin blood vessels and alveoli that allows gas exchange
o Oxygen goes from alveoli to the capillaries to oxygenate red blood cells (RBC)

Question 29

transport of gases

Answer 29

requires hemoglobin

Question 30

structure/function of hemoglobin

Answer 30

4 subunits and Heme group
§ 4 places for oxygen to bind
§ 2 places for CO2 to bind
§ When oxygen binds to Hb, CO2 doesn’t like to bind.
§ When CO2 binds to Hb, oxygen doesn’t like to bind.
§ Sigmoidal binding curve