COMPARATIVE COMPARATIVE ANATOMY:ANATOMY:ANIMAL BODY ANIMAL BODY SYSTEMS:SYSTEMS:RESPIRATORY SYSTEMRESPIRATORY SYSTEM

AISD - 2009

Respiratory SystemRespiratory System Function: to provide

oxygen gas need for cellular respiration and remove carbon dioxide from the body

Invertebrate Organs: ◦ gills and trachae

Main Vertebrate Organs: ◦ Nose, mouth, pharynx, larynx,

trachea, bronchi, bronchioles, lungs, gills, diaphragm

Respiration in animalsRespiration in animalsWhether they live in water or on land,

all animals must respire.◦ To respire means to take in oxygen and

give off carbon dioxide.Some animals rely of simple diffusion

through their skin to respire.While others…Have developed large complex organ

systems for respiration.

Invertebrate respirationInvertebrate respirationInvertebrate respiratory organs

have◦large surface areas◦Are in contact with air or water◦If require diffusion they must be

moist.

Aquatic invertebratesAquatic invertebratesAquatic animals have naturally moist

respiratory surfaces, and some respire through diffusion through their skin.◦ Example: jellyfish and anemones

Some larger aquatic animals like worms and annelids exchange oxygen and carbon dioxide through gills.◦ Gills are organs that have lots of blood

vessels that bring blood close to the surface for gas exchange.

Terrestrial InvertebratesTerrestrial InvertebratesTerrestrial invertebrates have respiratory

surfaces covered with water or mucus. (This reduces water loss)

There are many different respiratory specialized organs in terrestrial invertebrates. ◦ Spiders use parallel book lungs◦ Insects use openings called spiracles where air

enters the body and passes through a network of tracheal tubes for gas exchange

◦ Snails have a mantel cavity that is lined with moist tissue and an extensive surface area of blood vessels. How does respiration in aquatic invertebrates differ from

that in terrestrial invertebrates?

Section 29-2

Mollusk

Insect

Spider

Gill

Siphons

Movement of water

Booklung

Airflow

Trachealtubes

Spiracles

Figure 29–9 Invertebrate Figure 29–9 Invertebrate Respiratory SystemsRespiratory Systems

Vertebrate respiratory Vertebrate respiratory systemssystemsChordates have one of two basic

structures for respiration:◦Gills – for aquatic chordates

Example: tunicates, fish and amphibians◦Lungs - for terrestrial chordates

Examples: adult amphibians, reptiles, birds, and mammals

Aquatic GillsAquatic GillsWater flows

through the mouth then over the gills where oxygen is removed

Carbon dioxide and water are then pumped out through the operculum

Vertebrate lungsVertebrate lungsAs you move from amphibians to

mammals the surface area of the lungs increases ◦ Insures a greater amount of gas exchange

(or a two way flow of air).Birds, by contrast have lungs and air

sacs which have only a one-way flow of air. ◦ This allows for them to have constant

contact with fresh air. ◦ This adaptation enables them to fly at high

altitudes where there is less oxygen.

Section 33-3

Salamander Lizard PigeonPrimate

Nostrils, mouth, and throatTracheaLungAir sac

Figure 33–10: Vertebrate LungsFigure 33–10: Vertebrate Lungs

Section 37-3

Figure 37-13 The Respiratory SystemThe Human Respiratory The Human Respiratory SystemSystem

Section 37-3

Flowchart

Oxygen and carbon dioxide exchange at

alveoli

Oxygen-richair from

environment

Bronchioles

Nasalcavities Pharynx Trachea Bronchi

BronchiolesAlveoli

Pharynx Nasalcavities

Carbon dioxide-rich

air to the environment

Bronchi

Trachea

Movement of Oxygen and Carbon Movement of Oxygen and Carbon Dioxide In and Out of the Dioxide In and Out of the Respiratory SystemRespiratory System

BIG QUESTION

…WHY DO ANIMALS BREATHE?