Transcript Animals - Petal School District

Kingdom Animalia:
Animals
What makes it an animal?
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Multicellular
Eukaryotic
Heterotrophic
No cell wall
Have complex organs and systems
Can move at some point of their life cycle
Reproduction is primarily sexual
Divided into invertebrates and vertebrates
Types of Symmetry
Symmetry of organisms can be:
• Asymmetry—NO
particular body plan
• Radial—Body parts
arranged around a
central axis
• Bilateral—Right and
left halves are mirror
images of each other.
Anatomical Terms
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Anterior--Toward the front (head end)
Posterior--Toward the back or tail end
Dorsal--Back side
Ventral--Belly side
Medial--Toward the midline of the body
Lateral--Away from the midline of the body
Other Anatomical Terms:
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Proximal--Toward a reference point
Distal--Away from a reference point
Inferior--Lower or below
Superior--Upper or above
Cephalad or Cranial--Head
Caudal or Caudad—Tail or tail end
Invertebrates
No backbone!!!
Phylum Porifera
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Poriferans: Sponges
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Asymmetrical
Have pores through which water moves
Filter feeders
Sessile (can’t move) as adults
Hermaphroditic (both sexes in the same organism)
– Reproduction may be sexual or asexual
• Regenerates
• Regeneration—regrowth of a
lost or injured part of the
body (asexual)
Ex: A starfish cut in half
will grow into 2 starfish.
Picture: Planaria will
regenerate 2 heads
after being cut.
Phylum Cnidaria
Cnidarians
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Ex: hydras, jellyfish, sea corals, sea anemones
Radial Symmetry
Primarily marine
Nerve net – simple nervous system – whole body responds
One body opening
Nematocysts (stinging cells) for protection and food
gathering
• Two basic body plans - polyp (vase), medusa (inverted
umbrella)
Phylum Platyhelminthes
(Flatworms)
Platyhelminthes
(Flatworms)
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Ex: Planarian, grubs, tapeworms, flukes
Bilateral symmetry
Thin, solid bodies; 1mm to several meters long
Cephalization (one end functions as the head)
Digestive tract opens at only one end
True organs and systems
Most have both ovaries and testes
Some parasitic, others free-living
Regeneration
Phylum Nematoda
(Roundworms)
Nematodes
(Roundworms)
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Ex: hookworms, pinworms, Ascaris
Bilateral symmetry
Cephalization
Smaller than flatworms, tapered at both ends
(NO distinct head and tail)
• Two openings to the digestive tract; mouth and
anus
• Most are free living feeding on dead plant and
animal matter or Some are parasitic
• Found everywhere on earth
Phylum
Mollusca
Mollusks
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Soft-bodied
Bilateral symmetry
Ex: Clams, Snails, squid, oysters, and octopuses
Generally live in water
Some have a hard shell
Digestive system closed with only one opening
have a “foot” for gripping and creeping over
surfaces
• Gills
• Three major classes:
– gastropods (stomach-foot) – Ex: snails and slugs
– bivalves(two shells) – Ex: oysters, clams
– cephalopods (head-foot) – Ex: octopuses, squids
Phylum Annelida
(Segmented worms)
Annelids
(Segmented worms)
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Ex: earthworms, leeches
bilateral symmetry
cephalization
segmentation
two body openings
body systems
closed circulatory system
Are hermaphrodites
Phylum Arthropoda
Arthropods
(Means jointed foot)
• Largest group of invertebrates (more SPECIES)
• Bilateral symmetry
• External skeleton (Exoskeleton) – molts or sheds
to grow
• Segmented body
• Jointed appendages
• Antennae for sensing
• Respiratory structures may be: gills, tracheal
tubes, book lungs
Arthropods (cont.)
• 5 major classes:
– Centipedes (carnivores) – 1 pair of legs per segment
– Millipedes (herbivores) – 2 pairs of legs per segment
– Crustaceans (Ex: crab, shrimp, lobster, crawfish)
(Hard exoskeletons)
• 10 walking legs, stalked eyes
– Arachnids (Ex: spiders, ticks)
• Two body regions - fused head and thorax plus abdomen
• no antennae
• 8 legs
– Insects (largest group) (Ex: grasshoppers, butterflies,
beetles, cockroaches)
• live most everywhere, well-developed organs and senses, three
body segments (head, thorax, abdomen), some can fly
• May undergo metamorphosis
– egglarvaepupaeadult or eggnymphadult
• 6 legs, antennae, three body regions
Phylum Echinodermata
Echinoderms (Means spiny skin)
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Spiny skin for protection
Marine
Radial Symmetry
Ex: starfish, sea urchins, sand dollars, sea
cucumbers, brittle stars
Some can regenerate.
Internal skeleton (Endoskeleton)
Water vascular system (aids in movement,
gas exchange, excretion)
Embryo suggests ancestry common to
chordates
Phylum Chordata: Vertebrates
VERTEBRATES HAVE A BACKBONE!
(Some chordates are not vertebrates, though!)
• Chordates have:
– Notochord, which is a backbone in
vertebrates
– Nerve Cord
– Gill (or pharyngeal) slits at some stage of
development
• All have Bilateral Symmetry.
• Head, body cavity, digestive system, body
segmentation
There are three
classes of fish:
Class Agnatha: Jawless fish
Class Chondrichthyes:
Fish with Cartilage Skeletons
Class Osteichthyes: Bony Fish
Three Classes of Fishes
All Fishes:
•Aquatic
•Streamlined shape
•Functional tail that facilitates movement through water
•Most have gills.
•Scales or Skin
•Ectothermic
•2-chambered heart
Agnatha - jawless fishes—some parasitic
Ex: lampreys and hagfishes (are the only ones)
Chondrichthyes - Cartilaginous fish
Ex: sharks, skates, rays
Osteichthyes - Bony fish—Have a swim bladder
Ex: Bass, trout, goldfish
Class
Amphibia
Amphibians
• Undergo metamorphosis (egg—tadpole—
adult)
• Live both on land and in the water
• Ex: Frogs, toads, salamanders
• Fertilization is external.
• Skin
• Ectothermic
• 3-Chambered heart
Class Reptilia
Reptiles
• Ex: Lizards, snakes, crocodiles, alligators,
turtles
• Dry, scaly skin
• Most lay leathery eggs. (amniotic eggs)
• Some bear live young.
• Fertilization is internal.
• Lungs
• 3-chambered heart (Some 4-chambered)
• Ectothermic
Class Aves: Birds
Birds
• Adaptations for flight: hollow bones,
feathers, large sternum (breastbone)
which supports powerful flight muscles
• Feathers also insulate against loss of body
heat and water.
• Endothermic
• 4-chambered heart
• Air sacs to warm air before
it enters the lungs
• Bills or beaks
Class Mammalia
Three Subclasses of Mammals
Monotremes (egg-laying mammals)
Marsupials (Pouched Mammals)
Placental Mammals
Mammals
• Most complex of all animals - highly developed organ
systems and senses
• Have hair or fur
• Have mammary glands and feed their young milk
• Endothermic
• Three groups:
– Monotremes – egg-laying mammals – found in Australia and New Zealand
Ex: duck-billed platypus, spiny anteaters
– Marsupials - pouched mammals - young born prematurely
Ex: opossum, kangaroo, koala
– Placental mammals - most mammals – young nourished by
placenta until birth; born fully developed
Ex: rabbits, deer, dogs, cats, bats, whales, monkeys, and
humans