unit 8

Question 1

primary function of the respiratory system

Answer 1

exhcnage gasses with the environment to obtain suffiecient oxygen and sexrete suffiecient carbon dioxide

Question 2

ventilation

Answer 2

moving air or water across the gas exchange surface

Question 3

perfusion

Answer 3

pumping blood through the capillaries of an organ, in this case the capillaries of the gas exchange surface

Question 4

diffusion

Answer 4

spontaneous movement of molecules/atoms from a region of high concentration to low concentration

Question 5

adaptations to increase diffusion rate

Answer 5

large surface area
thin tissue
high vascularization

Question 6

dV/dt

Answer 6

diffusion rate. volume of gas moving through a given area in a given amount of time

Question 7

A/dx

Answer 7

A: surface area
dx: thickness of tissue

Question 8

D

Answer 8

constant diffusion rate

Question 9

(P1-P2)

Answer 9

partial pressure gradient.
P1: partial pressure of oxygen in the alveoli
P2: partial pressure of oxygen in the blood passing through the capillaries

Question 10

pathway of air in mammals

Answer 10

air is drawn through the trachea and enters the lungs through bronchi and bronchioles

Question 11

how do bronchioles end

Answer 11

tiny saccular compartments called alveoli

Question 12

what is special about the walls of alveoli

Answer 12

they are very thin and highly vascularized

Question 13

in actinopterygii, sarcopterygii, and chondrichthyes what provides skeletal support for the gills

Answer 13

pharyngeal arches 3-7 of the splanchnocranium

Question 14

gill rays

Answer 14

project from pharyngeal arches and support the interbranchial spetae

Question 15

elasmobranchii interbranchial septae

Answer 15

complete interbranchial septaw which separate the parabranchial chambers

Question 16

what creates the flap valve that covers the external gill slit

Answer 16

distal end of each interbranchial septum

Question 17

where do primary lamellae project from

Answer 17

both sides of the interbranchial septum

Question 18

what is on either side of the primay lamellae and what do they do

Answer 18

secondary lamellae. they are a site for gas exchange

Question 19

what are the small projections on pharyngeal arches 3-7

Answer 19

gill rakers

Question 20

what do gill rakers do

Answer 20

project into the pharynx forming a screen across the openings to the parabranchial chambers. this prevents food from entering these chambers and damaging the gills

Question 21

what taxa have gill rakers

Answer 21

chondrichthyes and actinopterygii

Question 22

where are elasmobranchs gills located

Answer 22

in parabranchial chambers

Question 23

what separates the parabranchial chamber

Answer 23

complete interbranchial septum

Question 24

where are actinopterygii gills

Answer 24

opercular chamber

Question 25

what type of gills do larval amphibians have

Answer 25

external gills

Question 26

tidal flow

Answer 26

not all the inhaled air reaches the gas exchange surface. not all of the air within the respiratory system is expelled during exhalation. some spent air remains such that the air inhaled during the following inhalation is a mix of the spent and fresh air

Question 27

unidirectional flow

Answer 27

all of the inhaled air or water passes over the gas exchange surface such that there is little to no dead space

Question 28

air breathing organs in actinopterygii

Answer 28

``` reinforced gills vascularized bucca or pharyngeal cavity buccal and pharyngeal diverticula specialized regions of the digestive tract swim bladder or lungs labrynth organ ```

Question 29

labyrinth organ

Answer 29

located dorsal to the gills. formed by extensive folding of one of the dorsal bones of the pharyngeal arch 3

Question 30

faclutatice breathing

Answer 30

actinopterygii and sarcopterygii have gills and air breathing organs. gills are used when there is lots of oxygen in water, and air is used when not lots of oxygen in the water

Question 31

obligate breathing

Answer 31

some actinopterygii and sarcopterygii. gills are greatly reduced so that even with lots of oxygen in the water the gills will not work for breathing, they need to access teh air to breathe.

Question 32

tetrapod breathing organs

Answer 32

lungs for air.

Question 33

small compartments in lungs

Answer 33

faveoli. all open into hollow chamber in the center of the lung

Question 34

how do amniotes ventilate their lungs

Answer 34

using an aspiration pump and tidal airflow

Question 35

archosaurs airflow

Answer 35

unidirectional. | thrachea branches into two primary bronchi, which branches into secondary bronchi. they are connected via parabronchi

Question 36

aves lungs

Answer 36

connected to a series of hollow elastic air sacs. expand when aspiration pump expands the thoracic cavity and compresses when aspiration pump compresses. parabronchi connects posterior air sacs to anterior