Download Invertebrate Animals (No backbone)

Invertebrate Animals
(No backbone)
I.
Kingdom Animalia Characteristics
A.
B.
C.
D.
II.
multicellular
eukaryotic
no cell wall
heterotrophic
Types of Symmetry
Describes the general orientation of how the body was “put together”
A. Asymmetry (no symmetry)- irregular body plan
Ex: sponges
B. Radial symmetry- Can be divided along any plane into equal parts, like
slicing a pizza into pieces or like the spokes of a wheel. Ex: jellyfish
and starfish
C. Bilateral symmetry- Animals that can be divided down the center
with the right-side being a mirror image of the left-side. Ex: worms,
insects, humans
III.
Phylum Porifera (pore-bearing)
Examples: mostly marine, some freshwater sponges
A. attached (sessile) as adults
B. Asymmetrical or radial symmetry
C. Pores (ostia) allow for passage of water
D. Filter-feeders
E. Collar cells with flagella
F. No tissues or organs (simplest of all animals)
G. Skeleton of calcium (rock), silicon (glass), or spongin (protein)
H. Asexual reproduction by buds or gemmules;
Sexual reproduction by eggs and sperm; free-swimming larvae
IV.
Phylum Cnidaria (Coelenterata)
Examples: hydra, jellyfish, Portuguese-Man-of-War, anemones, coral
A. Mostly marine; few freshwater
B. Radial symmetry; no definite head
C. Two body types
1. polyp- attached with tentacles stretched upwards
2. medusa- free-swimming with tentacles dangling down
D. Two body layers
E. Gastrovascular cavity with a single opening (mouth/anus)
F. Nematocysts=stinging cells
G. Nerve net
H. Simple muscular system
I. Reproduction-Asexual by budding; Sexual by production of eggs and sperm
J. No excretory system or respiratory system (gas exchange by diffusion)
V.
Phylum Platyhelminthes (Flatworms)
Ex: planaria, flukes, and tapeworms
A. Three body layers
B. Bilateral symmetry
C. Thick cuticle in parasitic forms (flukes and tapeworms)
D. Incomplete digestive system (one opening serves as both mouth and anus)
E. Simple nervous system with two nerve cords
F. Cephalization: nerves concentrated in the head region; simple brain
G. Simple senses; eye spots in planaria
H. Excretory system
I. Lack respiratory, circulatory, and skeletal systems
J. Most are one sex; must cross fertilize
K. Planarians are free-living; flukes and tapeworms are parasites
VI.
Phylum Nematoda (Roundworms)
Ex: hookworm, pinworm, intestinal roundworm, guinea worm
A. Three body layers
B. Bilateral symmetry
C. Has a cuticle
D. Slashing movement (forms “C’s” and “S’s”)
E. Muscular pharynx (throat)
F. Complete digestive system (separate mouth and anus)
G. Nerve ganglia (ball of nerves in head) act as a brain
H. Excretory system
I. Lack respiratory, circulatory, and skeletal systems
J. Many species are parasitic in humans
VII.
Phylum Molluska
Ex: snails, slugs, clams, oysters, squid, octopus, chambered nautilus
A. Bilateral symmetry
B. Definite head with mouth and sensory organs
C.
D.
E.
F.
G.
H.
Muscular foot (modified) used for locomotion
Mantle which covers body and sometimes secretes shell
Mucus glands
Complete digestive system (snails have a radula, or rasping tongue)
Respiration by gills or lungs
Open circulatory system in gastropods and bivalves; Closed circulatory system in
cephalopods
I. Excretory system
J. Advanced nervous system- highly developed eyes and brain in squid, octopus
K. Sense of touch, smell, and taste
L. Sexual reproduction
VIII.
Phylum Annelida (Segmented worms)
Ex: earthworms, leeches, sandworms, bristleworms
A. segmented bodies; repeating units
B. bilateral symmetry
C. setae- leg-like appendages in some
D. coelom- well developed body cavity
E. closed circulatory system- blood always contained within tubes
F. complete digestive system
G. Respiration by diffusion through skin or gills in some
H. Excretory system- nephridia in each segment
I. Advanced nervous system with a brain and ventral nerve cord
J. Sense organs include touch, taste, balance, light sensitivity in some
K. Separate sexes or hermaphroditic- sperm and eggs produced by one individual
IX.
Phylum Arthropoda (jointed appendages)
Ex: spiders, scorpions, ticks, mites, crabs, shrimp, lobsters, centipedes, millipedes, all
insects
A. bilateral symmetry
B. jointed appendages
C. exoskeleton made of chitin
D. Body regions
1. head, thorax, and abdomen OR
2. cephalothorax and abdomen
E. striated muscles
F. advanced digestive system
G. open circulatory system- blood seeps into body cavity
H. respiration- book lungs (spiders), spiracles and tracheal tubes (grasshoppers),
gills (crayfish)
I. excretory system- green glands
J. ventral nerve cord, simple brain
K. well developed sense organs- eyes, antennae, hearing, sensory bristles
L. separate sexes; internal fertilization
X.
Phylum Echinodermata (spiny skin)
Ex: starfish, sea cucumber, sea urchin, sea lily
A. radial symmetry
B. no head
C. endoskeleton (internal skeleton)
D. water vascular system
E. tube feet for locomotion in some
F. advanced digestive system
G. reduced circulatory system
H. respiration by water vascular system (diffusion), gills in some