COMPARATIVE ANATOMY: ANIMAL BODY SYSTEMS: RESPIRATORY SYSTEM AISD - 2009

AISD - 2009
COMPARATIVE ANATOMY:
ANIMAL BODY SYSTEMS:
RESPIRATORY SYSTEM
Respiratory 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 animals

Whether 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 respiration

Invertebrate respiratory organs have
◦ large surface areas
◦ Are in contact with air or water
◦ If require diffusion they must be moist.
Aquatic invertebrates

Aquatic 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 Invertebrates


Terrestrial 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?
Figure 29–9 Invertebrate Respiratory
Section 29-2
Systems
Gill
Tracheal
tubes
Siphons
Movement of water
Insect
Mollusk
Airflow
Spider
Book
lung
Spiracles
Vertebrate respiratory systems

Chordates 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 Gills


Water flows
through the mouth
then over the gills
where oxygen is
removed
Carbon dioxide
and water are then
pumped out
through the
operculum
Vertebrate lungs

As 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.
Figure 33–10:Vertebrate Lungs
Section 33-3
Nostrils, mouth, and throat
Trachea
Lung
Air sac
Salamander
Lizard
Primate
Pigeon
Figure 37-13 The Respiratory System
The Human Respiratory System
Section 37-3
Movement
of Oxygen and Carbon
Flowchart
Dioxide
In and Out of the Respiratory
Section
37-3
System
Oxygen-rich
air from environment
Bronchi
Trachea
BIG
QUESTION
…
Nasal
cavities
Pharynx
Trachea
Bronchi
Bronchioles
Oxygen and
carbon dioxide
exchange at
alveoli
Alveoli
Bronchioles
Pharynx
WHY DO ANIMALS BREATHE?
Nasal
cavities
Carbon
dioxide-rich
air to the
environment