I. Introduction
A. Kingdom
Animalia - the Animals
1. Multicellular,
aerobic heterotrophs
2. Nutrition from large molecules
a. Ingestion
- eating whole or in parts
b. Parasitism
- close relationship where parasite obtains nutrition from living
host
3. Bodies are diploid - only the gametes are haploid
4. Most animals are motile - move around as a result
of their own activity
a. Some
sessile - not motile and attached
b. Sessile
forms--mechanisms for dispersal - just like plants and fungi
B Invertebrates
= animals without backbones
C. A
group with great diversity
1. Many phyla
2. Possibly a result of multiple lines of evolution
from the Protista
a. Fossil
evidence from 800 million years in the form of tracks and burrows in
marine sediments
b. Ciliates--multiple
nuclei, then compartments
c. Colonial
flagellates with specialized cells
D. Body
symmetry
1. Asymmetrical - no specific or characteristic shape
2. Radial - parts arranged around a central axis
a. Through
the central axis in many planes and numerous equal halves
b. Usually
associated with sessile or very slow moving animals
c. Always
animals that live in water
3. Bilateral symmetry
a. Two
sides that are mirror images of each other (not perfect)
b. Two
ends - anterior and posterior
c. Usually
a "top and bottom" = the dorsal and ventral
d. Evolutionary
trend toward cephalization - a concentration of the sensory and
nervous control areas in the head (anterior) end which leads into the
environment
II. Placozoan
- plate animal
A. Soft
bodied and flat and a bit lumpy "like pita bread"
B. Cells
arranged in two layers
C. Specialized
cells migrate.
1. Lower layer with glandular cells which secrete
enzymes for digestion
2. What kingdom studied earlier with same manner?
D. Reproduction--unknown
F. One
known organism - Trichoplax adhaerens
III. Porifera
- the sponges
A. mostly
marine, a few are freshwater
B. Usually
asymmetrical
1. Outer layer of a flattened epidermis
2. Inner layer of choanocytes - collar cells
3. Non-cellular layer between which contains
a. amoeboid
cells - wandering cells
b. protein
fibers
c. spicules
- needles of calcium carbonate or silica
C. Two
layered body around one or more cavities
1. body wall is
perforated
2. beating flagella create current of water into the
cavity
3. food coming in with water is trapped on the collar
of the choanocytes
D. Reproduction
1. Sexual with eggs and sperm
2. Asexual by fragmentation (passive) or by production
of gemmules (protected groups of cells)
IV. Cnidarians
(tissue level) jellyfish, sea anemones, corals
A. Radial
symmetry
B. Body
Plan
1. Two cell layers
a. outer
epithelium - epidermis
b. inner
epithelium with digestive cells = the gastrodermis
2. Mesoglea - a thick proteinaceous separating layer
C. Specialized
cells of the tissues - a group of one type of cell--a particular
function
1. Neurons (but, not nerve cells)
2. muscle cells
3. secretory cells
4. cnidoblast cells that produce by secretion the
nematocysts
D. Body
forms
1. Polyp
a. column
like with ring of tentacles
b. central
body cavity
c. sometimes
with an external skeleton
d. sessile
2. Medusa - jellyfish
a. bell-shaped
with ring of tentacles
b. central
sack-like digestive area
c. swims
by contracting the bell rapidly
E. Life
Cycle
1. Medusa is sexual stage producing gametes
2. Fertilization produces a zygote which develops into
a planula larva
3. Settles and undergoes metamorphosis into a polyp
4. Variations
a. medusa
only
b. polyp
or polyps only (hydroids, sea anemones and corals
V. Platyhelminthes
- the flatworms
A. Bilateral
symmetry
B. Three
cell layers
1. Ectoderm
2. Mesoderm
3. Endoderm
C. Simple
organs - groups of one or more kinds of tissues arranged to perform a
specific function
D. Simple organ systems -
group of organs that perform a specific function
1. Digestive
2. Excretory
E. Reproduction
A. Sexual - are often Hermaphrodites
B. Asexual by fission
F. Classes
1. Turbellarians are free living in fresh and salt
water and occasionally in moist terrestrial conditions
2. Flukes
a. parasites
b. complex
life cycles of at least two hosts - one invertebrate and one
vertebrate (often humans)
3. Tapeworms
a. segmented
b. usually
are intestinal
c. multiple
host life cycles
VI. Nematoda
- roundworms (nema = “thread”)
A. Body
cavity within the mesoderm around the digestive system
1. Looks like a coelom
2. Specifically a pseudocoelom
B. Digestive
system with two openings
C. Hydrostatic
skeleton
D. Parasitic
and free living
E. Reproduction
1. Sexual only
2. Cell constancy (total number of body)
VII. Rotifera
- wheel animals
A. Jointed bodies
B. Pseudocoelom
C. complex
organ systems
D. Sexual
reproduction
1. Males and females
2. Parthenogenesis
a. female
populations
b. males
only when "needed"
WADSWORTH - CD
Porifera
5879
5884
5885 - 5892
5899
Cnidaria
5912 - 5944
Platyhelminthes
5951 - 5958
7039 - 7040 Flukes
7053 - 7065
Nematoda
7027
Rotifera
7068
