Comparative Comparative AnatomyAnatomy

Respiratory SystemRespiratory System

Note Set 10Note Set 10

Chapter 11 Chapter 11

Respiratory SystemRespiratory System

Gas exchange systemGas exchange system Oxygen and carbon dioxideOxygen and carbon dioxide

Fish- internal gills or lungsFish- internal gills or lungs Some amphibians- permanent Some amphibians- permanent

external gills (perennibranchiate)external gills (perennibranchiate) Others possess lungsOthers possess lungs

Accessory respiration Accessory respiration organsorgans Amphibian skinAmphibian skin

Figure 12.1: Adaptations for cutaneous respiration (hairy frog).

Fish Respiratory SystemFish Respiratory System

Gills associated with walls of Gills associated with walls of pharyngeal archespharyngeal arches

Internal gillsInternal gills Operculum- flap of skin covering gillsOperculum- flap of skin covering gills Spiracle- reduced 1Spiracle- reduced 1stst pharyngeal pharyngeal

arch openingarch opening NonfunctionalNonfunctional Not in higher fishNot in higher fish

Figure 12.2: Gills of shark and teleost.

Swim Bladder & LungsSwim Bladder & Lungs

Every vertebrate has lung Every vertebrate has lung diverticulumdiverticulum Pneumatic sacPneumatic sac

Which came first?Which came first? PhysoclistousPhysoclistous

Esophagus not connected to swim Esophagus not connected to swim

bladderbladder PhysostomousPhysostomous

Trachea to lungs or pneumatic sacTrachea to lungs or pneumatic sacFigure 12.3: Swim bladders and urodele lungs.

Lung diverticulum came firstLung diverticulum came first Then pneumatic duct in teleostsThen pneumatic duct in teleosts Swim bladder was possibly a secondary Swim bladder was possibly a secondary

modification of lungmodification of lung

Primitive Fish Have Primitive Fish Have Primitive LungPrimitive Lung

Figure 12.4: Evolution of lungs and swim bladders.

Swim BladderSwim Bladder

Red glands (gas glands)- network of Red glands (gas glands)- network of small arteriessmall arteries Provide oxygen to swim bladderProvide oxygen to swim bladder

Figure 12.6: Rete mirabile in fish, red indicates high oxygen concentration.

Figure 12.5: Swim bladder (red) of fish.

Swim Bladder Swim Bladder (cont.)(cont.)

Weberian ossiclesWeberian ossicles Swim bladder may act as sound Swim bladder may act as sound

chamberchamber

Figure 12.7: Weberian apparatus for transmitting swim bladder vibrations to ear.

Figure 12.8: Weberian ossicles.

Tetrapod LungsTetrapod Lungs Diaphragmatic muscles pull the liver posteriorly Diaphragmatic muscles pull the liver posteriorly

via an attachment to the posthepatic septum in via an attachment to the posthepatic septum in crocodilianscrocodilians

Most turtles also use diaphragmatic muscles to Most turtles also use diaphragmatic muscles to alter volume of cavity within the shell.alter volume of cavity within the shell.

Figure 12.9: Lower respiratory tract of bird.

Avian LungsAvian Lungs

Birds- modified lungs and ductsBirds- modified lungs and ducts Air sacs associated with lungsAir sacs associated with lungs Increase respiratory capacity for flightIncrease respiratory capacity for flight

TracheaTrachea

Passageway to lungsPassageway to lungs Larynx- voice box at Larynx- voice box at

headhead Laryngeal cartilagesLaryngeal cartilages Sound produced- vocal sacSound produced- vocal sac

Snake hissing- expulsion Snake hissing- expulsion of air from lungsof air from lungs

Figure 12.10: Human trachea and larynx (see book figure 13.13b).

TracheaTrachea

Birds- Syrinx instead of Birds- Syrinx instead of larynxlarynx Lower end of tracheaLower end of trachea Not homologous to larynxNot homologous to larynx Incapable of producing soundIncapable of producing sound

Mammals- man has larynxMammals- man has larynx Different cartilagesDifferent cartilages Epiglottis over glottis to Epiglottis over glottis to

larynxlarynx Diaphragm Diaphragm

Figure 12.11: Asymmetrical bronchotracheal syrinx of duck (book figure 13.16).

Accessory Respiratory Accessory Respiratory OrgansOrgans

Yolk sacYolk sac In embryo In embryo

SkinSkin Many fish and amphibiansMany fish and amphibians Ex: African Clawed frog (Ex: African Clawed frog (XenopusXenopus)- chin )- chin

barbelsbarbels Rectum & CloacaRectum & Cloaca

Highly vascularized in some fishHighly vascularized in some fish Ex: Aquatic turtlesEx: Aquatic turtles

Literature CitedLiterature CitedFigure Figure 12.1 & .1 & 12.4: Kardong, K. Vertebrates: Comparative Anatomy, .4: Kardong, K. Vertebrates: Comparative Anatomy,

Function, Evolution. McGraw Hill, 2002. Function, Evolution. McGraw Hill, 2002. Figure Figure 12.2, .2, 12.3, .3, 12.7, .7, 12.9 & 12.11: Kent, George C. and Robert K. .9 & 12.11: Kent, George C. and Robert K.

Carr. Comparative Anatomy of the Vertebrates. 9th ed. McGraw-Carr. Comparative Anatomy of the Vertebrates. 9th ed. McGraw-Hill, 2001.Hill, 2001.

Figure Figure 12.5: .5: http://www.palaeos.com/Vertebrates/Lists/Glossary/GlossaryWZ.hthttp://www.palaeos.com/Vertebrates/Lists/Glossary/GlossaryWZ.html#Wml#W

Figure Figure 12.6: .6: http://www.palaeos.com/Vertebrates/Lists/Glossary/GlossaryC.htmlhttp://www.palaeos.com/Vertebrates/Lists/Glossary/GlossaryC.html

Figure Figure 12.8: http://www.voiceproblem.org/anatomy/learning.asp .8: http://www.voiceproblem.org/anatomy/learning.asp Figure Figure 12.10: http://www.voiceproblem.org/anatomy/learning.asp.10: http://www.voiceproblem.org/anatomy/learning.asp