The Cladogram of Animals
Main Topics
I.
II.
III.
IV.
General Characteristics
Sponge Anatomy- The Basics
Feeding and Reproduction
Types of Sponges
I. General Characteristics
• Porifera- Latin for
“pore-bearing;”
contain pores all
over their body
• Simplest
multicellular
animals (most
primitive)
• Invertebrates
General Characteristics (continued)
Levels of
Organization
Specialized cells,
no true tissues
Body Symmetry
Asymmetrical
Germ Layers
Absent
Body Cavity
-
Embryological
Development
-
Segmentation
Absent
Cephalization
Absent
General Characteristics (continued)
• Can be better described
as a colony of single
celled organisms living
together
• Over 10,000 species; all
aquatic and 99% marine
• All are filter feedersfilter small particles of
food from water that
passes through the
organism
General Characteristics
• Some defend
themselves with
chemicals and are
focus of biotech
research companies
• Adults are sessile- live
permanently attached
to a substrate (base
material like a reef or a
crab) and are not able
to move on their own
Current Event Homework
• Find an article about how Poriferans (sponges)
are used in biomedical research.
• Due Friday
Requirements:
1. Print a copy of the article
2. On a separate paper, write a summary of the
article.
3. Counts as a double Homework assignment
II. Sponge Anatomy- The Basics
• “Vaselike” general
shape
• Osculum- one large
excurrent pore where
water flows out of
• Ostium- many tiny,
incurrent pores where
water flows in (plural
Ostia); found
throughout the body
• Atrium- inner filter
chamber
Oscula
Holdfast- root-like
structure that
anchors aquatic
sessile
organisms, such
as seaweed and
sponges
II. Sponge Anatomy- The Basics
• Wall of the body is made of 3 cell layers (remembernot true germ layers)
Outer Layer
• Lined with
Pinacocytesflattened
cells packed
tightly
together that
forms the
outer
boundary
Sponge Anatomy- The Basics (continued)
Gelatinous layer
• Middle layer that forms
the skeleton and support
for the sponges shape
• Amebocytes- cells carry
food and oxygen to
cells of each layer
• Spicules- needle-like
structures made of silica
or calcium
• Spongin- tough protein
fibers
Sponge Anatomy- The Basics (continued)
Inner Layer
• Lined with
choanocytes (collar
cells)- specialized cell
that has a flagella.
These cells help
control water flow into
and out of the cell.
• The flagella beats to
create water current
and the collar traps
food particles.
III. Feeding and Reproduction
• Mostly feed on
plankton and organic
molecules
Feeding and Reproduction (continued)
1. Water enters through
ostia.
2. Water is pumped into
the atrium.
3. Collar cells trap food
particles with flagella.
4. Amebocytes take food
to other cells within the
sponge.
5. Water leaves through
the osculum.
Figure 12.07
Figure 12.09
Feeding
• http://www.youtube.com/watch?feature=pl
ayer_detailpage&list=PL6174CA65320048
CE&v=RmPTM965-1c
Feeding and Reproduction (continued)
Sponges reproduce both asexually and sexually.
Asexual
Branches or buds break off &
grow into separate sponges
(budding)
Sexual
Sponges produce both male
& female gametes to produce
larva. Larvae floats off and
establishes itself on a new
base.
Asexual Repro Budding
• http://www.youtube.com/watch?v=4JIytOLQ18&feature=player_detailpage
IV. Types of Sponges
• There are 3 major Classes of sponge.
• Sponges are classified mainly based on
what their skeleton is made of in the
gelatinous layer.
• Common names are mainly based on their
shapes
• Non-synthetic cleaning sponges have
spongin skeletons; Synthetic sponges are
made based off spongin skeletons