CVA: Respiration

Respiratory

gas exchange w environment

Circulatory system

transport w/in body

Respiration system relies on

diffusion

Gills take the look of

dense capillary beds supported by branchial skeleton (arches)

Int. gills, aka pharyngeal slits/ pouches are often covered by

bone (operculum) or integument

Ext. gills protrude out of body but are also found in many

larvae, few adults

Gas bladder have evolved for

buoyancy, gas exchange

Lungs are

bladders evolved for breathing

Swim bladders are

evolved for buoyancy control

While lung are ventral, swim bladders are

dorsal to gut

Cutaneous repiration

breathing through skin

Cilia fucntion

Move water in small animals, clean air channels in larger animals

Water dual pump

2 stroke pump sys used by MOST fish

Air buccal pump

mouth and throat muscles PUSH air into lungs

Air aspiration pump

lungs expand to PULL air in

Unlike Gnathostomes, Agnathans’ gills are

MEDIAL to branchial arches

Lung septal

subdivided by partitions to inc surface area

Faveolus/ Faveoli

compartments amphibian lung/ like small pockets of the lungs

Unlike amphibians, MOST reptiles use

an aspiration pump, squeezing air in

Mammals have Alveoli which are

blind-ended compartments that max surface area

For mammals, what drives aspiration pump?

the Diaphragm

Birds are weird, what do they have instead?

a unique one-way reparatory

Parabronchi

tiny 1-way airways w/in lungs

Air sacs are

avascular structures connected to lungs, tucked among viscera, extended into large bones

W/in birds, having a 4-stage pump maintains—

a continuous air flow across lungs

Such parabronchi and air capillaries found w/in birds create a

cross-current exchange

Fish max gas exchange via

countercurrent exchange, the most efficient way of exchange [35:1]

Reptiles and mammals max gas exchange via

uniform pool

Birds max gas exchange via

cross-current exchange

Alveolar

sac-like compartments in mammals w/ greater SA, elasticity

Faveolar (faviform)

spaces formed by septa, subdivision not resulting from bronchial tree

Parabronchia

blind sacs surround and open to central parabronchus