Respiratory Systems

Question 1

What are respiratory organs?

Answer 1

surfaces that capture O2 and release CO2

Question 2

How to determine how much O2 is available?

Answer 2

Concentration
Partial Pressure
Respiratory Media

Question 3

What is concentration?

Answer 3

the amount of gas in a mixture

Question 4

What affects concentration?

Answer 4

temperature
altitude
salinity

Question 5

What is partial pressure?

Answer 5

the pressure exerted by gas in a mixture

determines diffusion by looking at gradient between high and low partial pressure in a system

Question 6

What does partial pressure allow?

Answer 6

exchange of gases across cell membranes

Question 7

How is partial pressure calculated?

Answer 7

concentration x barometric pressure

Question 8

What is total barometric pressure?

Answer 8

the sum of all partial pressures of the different mixed gases

Question 9

What are the two respiratory medium?

Answer 9

water (less O2 available due to higher viscosity and lower solubility
and air (more O2 available due to lower viscosity)

Question 10

What do respiratory organs need?

Answer 10

moisture: plasma membranes need to contract with aqueous solution for diffusion
large surface area: to conduct enough gas exchange via skin, gills, lungs and/or tracheae

Question 11

What animals use skin as a respiratory system?

Answer 11

annelids and amphibians

Question 12

What animals use tracheae as a respiratory system?

Answer 12

insects

have tiny branching tubes that penetrate body bringing O2 directly to body cells

Question 13

What are gills?

Answer 13

extensive out-folding of body that create a large surface area for gas exchange

Question 14

What is ventilation in gills?

Answer 14

movement over the respiratory surface, is required to maintain pressure gradients

Question 15

What is countercurrent exchange in fish?

Answer 15

blood flows in opposite direction of water passing over gills
ensures that water always has higher O2 partial pressure than blood

Question 16

What are lungs?

Answer 16

derived from the gut in development and are subdivided into numerous pockets
they need a circulatory system that transports gases between the lungs and rest of the body
most species are vertebrates, spiders, and snails

Question 17

Describe the steps of the mammalian respiratory system.

Answer 17

1: air enters the nostrils to get filtered, warmed and humidified in the nasal cavity
2: air moves to the pharynx, where it proceeds through the larynx
3: air passes the epiglottis/esophagus, and moves down the trachea
4: trachea branches into two bronchi, one leading to each lung
5: bronchi branch repeatedly in each lung, into finer-and-finer tubes called bronchioles

Question 18

What do the smallest bronchioles have?

Answer 18

air sacs clustered at their tips called alveoli

Question 19

What happens at the alveoli?

Answer 19

gas exchange between the epithelial cells and senses capillaries

Question 20

What do alveoli lack?

Answer 20

cilia and mucus for protection

Question 21

What does the surfactant film do?

Answer 21

protects alveoli and reduces surface tension to keep sacs open

Question 22

How does gas exchange occur?

Answer 22

O2 rapidly diffuses across the epithelium into capillaries and the circulatory system
CO2 rapidly diffuses from the capillaries, across the epithelium and into alveoli

Question 23

What is breathing?

Answer 23

the process that conducts ventilation with alternation of inhalation and exhalation

Question 24

How does the thoracic cavity move during breathe?

Answer 24

expands during contraction of rib cage, moves down

relaxes during exhalation and moves up

Question 25

What is negative pressure breathing?

Answer 25

expansion pulls air into lungs

Question 26

What is tidal volume?

Answer 26

the volume of air inhaled with each breath

Question 27

What is vital capacity?

Answer 27

the maximum tidal volume for the lungs

Question 28

What is residual volume?

Answer 28

the air that remains in the lungs

Question 29

What is hemoglobin?

Answer 29

what most vertebrates and some invertebrates use to move O2

produced by red blood cells

Question 30

What is needed in hemoglobin?

Answer 30

essential mineral: Fe, iron to build a functional heme group needed to carry O2
has four chains that can each bind to an O2 molecules

Question 31

What is cooperative binding?

Answer 31

each addition of a bond becomes easier, the first bond always requires the most energy

Question 32

What does the dissociation curve of hemoglobin show?

Answer 32

that the protein also can release O2 in response to just small changes in partial pressure

Question 33

How are blood pH and hemoglobin efficiency related?

Answer 33

Increase in pH decreases hemoglobin efficiency

Question 34

What does blood play a role in?

Answer 34

CO2 produced by cellular respiration helps lower affinity for O2

Question 35

When is the partial pressure of blood different?

Answer 35

Low partial pressure of O2 when blood arrives in lungs

High partial pressure of CO2 when blood arrives in lungs