Download Animal Phyla

Objectives

Distinguish between 9 major phyla in
the animal kingdom
– Distinguish between kinds of symmetry
– Distinguish between kinds of skeleton
– Know the different levels of organization
– Recognize segmentation
Symmetry

We’ll be differentiating between several
phyla based upon symmetry. There
are three kinds of body organization
symmetry you must know.
– First, what is symmetry?
Symmetry

We’ll be differentiating between several phyla based
upon symmetry. There are three kinds of body
organization symmetry you must know.
– First, what is symmetry? Generally, a symmetric shape is a
shape that still looks the same if you fold or rotate it.
– Write down each definition, then, mold your playdoh into an organism that models that kind of
symmetry.
– Check with me that you’re correct, then draw
what you’ve made next to the definition.
Symmetry

Asymmetric: Irregular. Is not
symmetric.

Create an asymmetric organism.
– Check your work with me, then draw it.
Symmetry

Bilateral Symmetry: The organism can
be divided into mirror-image halves.
Symmetry

Radial Symmetry: Cutting/folding
down several planes would produce
identical pieces. Radially symmetric
organisms don’t have a lateral axis.
Symmetry

Real-life examples of the three kinds of
symmetry?
– Asymmetry
– Bilateral symmetry
– Radial symmetry

(Note: No organism is 100% perfectly
symmetric, there are always “imperfections.”
These describe the general body plan.)
Skeleton Types

Animal phyla are also divided by the
type of skeleton involved.
– Write the definitions. Then, together, see
if you can think of an animal that uses this
kind of skeleton. Mold your clay into it.
Skeleton Types

Hydrostatic Skeleton: The organism
does not have a “true” skeleton, it uses
a fluid-filled cavity and/or fluid
environment to maintain its shape.
Skeleton Types

Exoskeleton: The animal’s body is
supported and its shape maintained by
an external skeleton.
Skeleton Types

Endoskeleton: The animal’s body is
supported and its shape maintained by
an internal skeleton.
Levels of Organization

The most basic level of organization is
a cell. The cell is the smallest selfcontained unit that fulfills all the
characteristics of life.
– Animals are made of more than one cell.
However, they vary in the complexity of
how those cells work together.
Levels of Organization



A tissue is a group of cells that work together
to carry out a specific function.
An organ is a group of tissues that work
together to carry out a general function.
An organ system is a group of organs that
work together to carry out a major function.
– Some organisms may have organ systems,
others may be simpler, some may not even have
tissues.

http://micro.magnet.fsu.edu/primer/java/scie
nceopticsu/powersof10/
Segmentation


Finally, you’ll need to know what
segmentation is.
Segmentation is the division of a body
plan into a series of semi-repetitive
segments.
– Please mold your play-doh into a body
plan showing segmentation.
Animal Phyla

I’ll teach you the general characteristics of 9
animal phyla. For each phylum:
– Fill out your table with the characteristics of that
phylum


Make note of what sets it apart from the other phyla
You’ll later make a dichotomous key for use in
identifying animal phyla
– Mold your play-doh into an animal you think is
representative of that phylum


Check with me to see if you’re right
For every three phyla that you make a correct mold of
on the first try, you get a sticker.
Animal Phyla


PORIFERA
These sessile (non-moving) marine
animals are:
– Asymmetrical
– Lack true tissues, no organs or organ
systems
– Not segmented
– Hydrostatic skeletons
– Reproduce sexually or asexually
(fragmentation)
Animal Phyla

PORIFERA
– Sponges!
~8000 known species
 First emerged ~1 bya
 Includes 3 classes

QuickTime™ and a
decompressor
are needed to see this picture.
QuickTime™ and a
decompressor
are needed to see this picture.
QuickTime™ and a
decompressor
are needed to see this picture.
Animal Phyla

CNIDARIA
– These mostly motile (capable of
movement) marine animals are:
Radially symmetrical
 Have tissues but not true organs
 Not segmented
 Hydrostatic skeletons
 Reproduce sexually or asexually
 “Mouths” surrounded by stinging tentacles

QuickTime™ and a
decompressor
are needed to see this picture.
Animal Phyla

CNIDARIA
– Jellyfish, sea anenomes, and corals!
More than 9000 species
 Two-stage life cycle, medusa and polyp
 First emerges 580 mya
 Characteristic cnidocytes, stinging cells

QuickTime™ and a
decompressor
are needed to see this picture.
QuickTime™ and a
decompressor
are needed to see this picture.
Animal Phyla


PLATYHELMINTHES
Motile, land- or water-dwelling animals that
are:
–
–
–
–
–
–
Bilaterally symmetrical
Have organs and a couple organ systems
Not segmented
Hydrostatic skeleton
Reproduce sexually
Have only one opening to/from their digestive
system
QuickTime™ and a
decompressor
are needed to see this picture.
Animal Phyla


QuickTime™ and a
decompressor
are needed to see this picture.
PLATYHELMINTHES
Flatworms!
– More than 25,000 known species, most of
which are parasitic
– Mostly hemaphroditic
– No circulatory or respiratory system; they
are flat so that gases can diffuse to and
from any cell in their body
QuickTime™ and a
decompressor
are needed to see this picture.
QuickTime™ and a
decompressor
are needed to see this picture.
QuickTime™ and a
decompressor
are needed to see this picture.
Animal Phyla


NEMATODA
Motile land- or water-dwelling animals
that are:
– Bilaterally symmetrical
– Have organ systems
– Not segmented
– Hydrostatic skeleton
– Reproduce sexually
– Have two digestive system openings
QuickTime™ and a
decompressor
are needed to see this picture.


Animal Phyla
QuickTime™ and a
decompressor
are needed to see this picture.
NEMATODA
Roundworms!
– More than 28,000 species described,
estimated more than 500,000 species
exist
– Over half are parasitic. Some parasitize
animals, others parasitize plants.
– Includes C. elegans, a worm made of just
959 cells, one of the most important
species to modern biology
QuickTime™ and a
decompressor
are needed to see this picture.