Download Animal Kingdom: Comparative Anatomy

Lecture 20: Anatomy
A.Collins
JSHS
Pre-AP Biology
What do animals do to survive?
Section 26-1
All
Animals
have
are
carry out
Eukaryotic
cells
Heterotrophs
Essential
functions
with
such as
No cell walls
Feeding
Respiration
Circulation
Excretion
Response
Movement
Reproduction
Invertebrate feeding and digestion
 Invertebrates can either have intracellular or
extracellular digestion:
 Intracellular meaning that food is digested within each
individual cell of the organism.

Examples: Sponges
 Extracellular means that digestion occurs inside a
digestive tract or cavity, then absorbed into the body.

Examples: mollusks, worms, arthropods, echinoderms
Section 29-2
Invertebrate Digestive Systems
Intestine
Gizzard
Crop
Mouth/anus
Pharynx
Mouth
Gastrovascular
cavity
Annelid
Anus
Gastrovascular
cavity
Cnidarian
Pharynx
Crop
Arthropod
Anus
Pharynx
Mouth
Mouth/anus
Flatworm
Stomach
and
digestive glands
Rectum
Intestine
Vertebrate Digestive Systems
 The digestive systems of many vertebrates have
organs that are well adapted for different feeding
habits.
 Carnivores, such as sharks have short digestive
tracts that produce fast-acting digestive enzymes.
 Herbivores have long intestines that have large
colonies of bacteria that help in digesting the
cellulose fibers in plant tissues.
Section 33-3
The Digestive Systems of Vertebrates
Esophagus
Stomach
Intestine
Liver
Gallbladder
Pancreas
Cloaca
Crop
Gizzard
Cecum
Rectum
Shark
Salamander
Lizard
Pigeon
Cow
Respiration in animals
Aquatic invertebrates
 Aquatic animals have natural moist respiratory surfaces, and some
respire through diffusion through their skin and others use gills.
Terrestrial Invertebrates
 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.
Section 29-2
Invertebrate Respiratory Systems
Tracheal
tubes
Gill
Siphons
Movement of water
Spiracles
Insect
Mollusk
Airflow
Spider
Book
lung
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
Section 33-3
 Carbon dioxide and water are then pumped
out through the operculum
Vertebrate Lungs
Nostrils, mouth, and throat
Trachea
Lung
Air sac
Salamander
Lizard
Primate
Pigeon
Invertebrate Circulatory systems
 Invertebrate circulatory system can range from a system
where cells simply do diffusion to take in oxygen or systems
with many hearts and even systems with one heart.
Open circulatory systems
 Blood is pumped through a system of vessels BUT is only partially contained in
these vessels. Most of the time the blood is pumped through open cavities.
 This system is beneficial to arthropods and mollusks because the blood comes into
direct contact organs and tissues.
Closed circulatory systems
 A closed system forces blood through vessels that extend throughout the body
of the organism. Since the system is “closed” the blood never leaves the vessels.
 This system is beneficial to larger organisms because the blood is kept at a higher
pressure which allows for more efficient circulation within the organism.
Section 29-2
Invertebrate Circulatory Systems
Heartlike structure
Hearts
Small vessels in tissues
Heart
Blood
vessels
Sinuses
and organs
Heartlike
structures
Insect:
Open Circulatory System
Annelid:
Closed Circulatory System
Blood
vessels
Vertebrate circulatory systems
 Chordate circulatory systems range from a single loop system (found in
organisms with gills) to double loop systems.
Double-Loop Circulatory System
Single-Loop
Circulatory System
FISHES
MOST REPTILES
CROCODILIANS, BIRDS,
AND MAMMALS
Aquatic Invertebrate excretion
 Some aquatic invertebrates simply diffuse ammonia out their bodies
into the surrounding water where it is diluted and carried away.
 Example: sponges, cnidarians, and some round worms.
 Other aquatic invertebrates swell up with water, dilute the wastes and
excrete the wastes through tiny pores in their skin.
Terrestrial Invertebrate excretion
 Many terrestrial invertebrates convert ammonia into urea.
 Urea is a simpler nitrogenous compound that is much less toxic
than ammonia.
 This urea is eliminated from the body in urine
Section 29-2
Invertebrate
Excretory Systems
Flame
cells
Flatworm
Excretory
tubules
Nephrostome
Excretory pore
Flame cell
Excretory tubule
Nephridia
Digestive tract
Annelid
Arthropod
Malpighian
tubules
Vertebrate Excretion
 Aquatic vertebrates kidneys and
rely on gill slits to release
excretory wastes into
surrounding water for dilution.
 Terrestrial vertebrates rely on the
kidney’s to filter out the
ammonia and change it into urea
and send it to be released in
urine.
Nervous system
 All animals respond to their environment through
specialized cells called nerve cells.
 In most animals nerve cells hook together to form
the nervous system.
 Nervous systems can range from fairly simple to
extremely complex.
 The arrangement of nerve cells from phylum to
phylum can be dramatically different.
Section 29-2
Invertebrate Nervous Systems
Arthropod
Brain
Ganglia
Ganglia
Brain
Flatworm
Mollusk
Vertebrate Nervous Systems