Transcript Invertebrate Unit (Ch. 26, 27, 28, 29)

Aquatic Life –
Invertebrate Animals
In this unit we will introduce
characteristics of aquatic
organisms and focus on
invertebrate animals (that
lack a backbone).
Photo Credit:
Photograph by Chris Newbert/Minden Pictures
Characteristics of Animals
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All animals are
eukaryotic; their
cells have a nucleus
and specialized
organelles.
Their cells DO NOT
have cell walls,
differentiating them
from bacterial and
plant cells.
All animals are
multicellular.
Because animals
cannot make their
own food they are
considered
heterotrophs .
Essential Functions
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http://photography.nationalgeographic.com/photography/photo
s/schools-fish/school-of-grunt-fish-photography.html
Homeostasis
Feeding/Excretion
Support/Movement
Respiration/
Circulation
Response to
Environment
Reproduction
Feeding and Excretion
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http://photography.nationalgeographic.com/photography/photos/colorful-seacreatures/pygmy-seahorse-doubilet.html
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Animals must find,
consume, and digest food
for energy.
They must also get rid of
waste products.
Just as the machines in a
factory produce waste, the
cells of organisms often
produce a “trash”
substance called ammonia
which is poisonous.
The excretion (to get rid of)
of wastes from the body
varies between organisms.
Support & Movement
http://photography.nationalgeographic.com/photography/photos/und
erwater-scenes/basket-sea-star-photography.html
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Most animals are active and require energy for movement.
Some animals are sessile, or permanently attached to one spot
(EX sponges).
Most animals are motile and are free-moving at some time in
their life cycle (which allows offspring to settle in a new place).
Some animals are passive and move only when carried by another
force such as water currents or wind.
Respiration & Circulation
http://www.tunalab.unh.edu/IMAGES/gills.jpg
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Animals must have oxygen to release energy within cells.
Some animals use lungs while some aquatic animals use gills
to bring in oxygen and get rid of the CO2 by product of cellular
activity.
Others use diffusion to pass the gases in and out of their body.
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Animals must be aware of their environment to obtain
food, seek protection from predators, find mates and
reproduce, etc.
Animals respond to their environment using
specialized nerve cells to sense external stimuli (light,
sound, etc) and to process information.
EX The shark using senses.
http://photography.nationalgeographic.com/photo
graphy/photo-of-the-day/shark-kingman-reefpod.html
Response
Reproduction
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http://z.about.com/d/biology/1/0/-/2/pbear.jpg
Animals must
reproduce to
maintain the species.
Most reproduce
sexually using sperm
and an egg.
Some can reproduce
asexually (from just
one parent).
Animal Body Symmetry
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Radial symmetry –
arrangement of body
parts around a central
point (EX starfish).
Bilateral symmetry –
arrangement of body
parts along a plane (EX
heart, centipede).
Asymmetry – lack of
symmetry (EX sponge).
http://www.biologycorner.com/resources/sy
mmetry_comparison.gif
Invertebrates vs. Vertebrates
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The animal
kingdom is divided
into two main
groups:
Invertebrates –
without backbones
Vertebrates – with
backbones
http://www.bbc.co.uk/schools/revisewise/images/science/liv03b/03bfimg1.gif
Phylum Porifera
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http://www.lpdatafiles.com/data/mso2003/SCUBA%20SPONGES.jpg
Sponges are the
oldest and simplest
and probably most
unusual animals,
classified in the
Phylum Porifera.
Name means “porebearer” and are
often seen in their
dried form as
natural sponges
used for bathing.
Sponge Characteristics
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Sponges are sessile
organisms that do not
move (as adults).
No symmetry (asymmetry)
Sponges lack special
tissues and organs.
They have special
structures that allow water
to pump through their body
which help the sponge to
respire and filter food and
excrete waste.
Sponge Video
http://www.scubaheartland.com/photos/sponges.jpg
Phylum Cnidaria
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http://san-pedro-aquarium.california-california.info/Cnidarians.gif
Think floating
jellyfish and sea
anemones (home to
Nemo)!
Found in water all
over the world,
Phylum Cnidaria (C is
silent) are soft
bodied, carnivorous
animals that have
stinging tentacles.
Cnidarians link
Cnidarians Characteristics
http://www.mbgnet.net/salt/animals/1coral.jpg
http://www.hawaiisfishes.com/inverts/cnidarians/Anomal
orhiza_shawi.JPG
Cnidarians Cont.
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http://www.corkvisioncentre.com/corkvisioncentre/Imag
es/Underwater-Realm-2.jpg
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Cnidocytes – unique
cells that contain
stinging, poisonous
barbs that are used to
capture prey found on
their tentacles.
The display radial
symmetry.
Reproduce sexually or
asexually (1 way) by
budding
Cnidarians make up
the world’s coral reefs
and float along with
currents.
Stunning Jelly (Search
jellyfish)
Cnidarians Examples
http://www.ucihs.uci.edu/biochem/steele/Physalia.htm
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Cnidarian Video
http://www.ima
gequest3d.com
/photos/combje
llies/index.htm
Phylum Platyhelminthes –
Flatworms are classified
Flatworms
as part of the Phylum
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http://www.ucmp.berkeley.edu/platyhelminthes/pseudobiceros.jpg
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Platyhelminthes.
Flatworms are unsegmented (no rings)
and appear flat, most no
more than a few
millimeters thick.
They have tissues and
internal organs systems,
bilateral symmetry, and
cephalization (which
means they have a
head!)
Flatworm video
Flatworm Characteristics
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They have a single
digestive opening, a
Mouth/Anus in which
food enters and
undigested waste
leaves.
Because they are so
thin, most flatworms
do not need a
circulatory system to
transport materials,
but use diffusion.
Respiration also
occurs through
diffusion.
http://www.emc.maricopa.edu/faculty/farabee/biobk/flatworm.gif
Flatworms Cont.
http://biology.ucok.edu/AnimalBiology/Platyh
elminthes/tapeworms.jpg
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They move to obtain food and escape predators.
They can be both carnivorous or parasitic (this tapeworm lives
inside the human intestines).
Phylum Nematoda/Nemertea –
Roundworms
Also known as
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http://www.robots4farms.com/scubadivingpictures_files/daphneislet_files/99_jms_RoseRibbonW
orm_90p_P2250080.jpg
roundworms,
Phylum Nematoda
consists of
unsegmented
worms that can be
microscopic or a
large as a meter in
length!
Most roundworms
are free living and
are found in the soil,
the sea floor, or
water.
Others are parasites
that live in plants
and animals.
Phylum Annelida – Segmented
http://www.corbisimages.com/images/67/CC068D92-8C8A-4D6F-AC05-0092B9A74CF7/FL006311.jpg
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Think earthworms and leeches!
Phylum Annelida consists of the common earthworm and
is characterized by worms with segmented bodies.
The name means “little rings”.
Worm Video
Phylum Mollusca
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Think snails, clams, and the octopus!
Mollusks are characterized by soft bodies that is sometimes
protected by a hard shell.
http://www.greenfacts.org/images/
glossary/mollusk.jpg
Mollusks Cont.
http://www.uni-giessen.de/uni/broschuere/FB08-Nautilus.jpg
Classes of Mollusks
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http://www.go
chart.com/dig
_photo/clams
.JPG
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http://www.saczoo.
com/3_kids/20_ca
mouflage/images/o
ctupus.jpg
Kingdom Animalia / Phylum
Mollusca / Class…
Class Polyplacophora (Chitons
– most primitive mollusks)
Class Gastropoda (mollusks
with shells; EX snails)
Class Bivalva (mollusks with a
hinged shell; EX clams and
oysters)
Class Cephalopoda (advanced,
intelligent mollusks; EX
nautilus, squid, octopus,
cuttlefish which have a closed
circulatory system)
Phylum Echinodermata
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Think starfish (sea stars) ,
sand dollars, and sea
urchins!
Phylum Echinodermata
means "spiny skin“ and
these organisms live only
in the ocean.
Echinoderms have the
ability to regenerate their
limbs.
http://www.museums.org.za/bio/images/mb/mb0556x.jpg
Echinoderms Cont.
http://www.wetwebmedia.com/ca/cav1i4/echinoderms/sea_apple.jpg
These are the elaborate
filter-feeding tentacles of a
Sea Apple.
Echinoderms Cont.
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Kingdom Animalia /
Phylum Echinodermata /
Class…
Class Asteroidea – sea
stars or starfish
Class Ophiuroidea – brittle
stars and basket stars
Class Echinoidea – sea
urchins and sand dollars
Class Holothuroidea – sea
cucumbers
Class Crinoidea – sea lilies
and feather stars
http://www.cse.ucsc.edu/~ejw/tatum/images/urchins.jpg
Phylum Arthropoda
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http://content.answers.com/main/content/wp/en/th
umb/9/99/150px-Zorak-Mantis.png
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The butterfly, the spider, and the
shrimp all belong into the Phylum
Arthropoda, which means “jointed
feet”.
Characterized by bilateral
symmetry, they have segmented
bodies fused into larger body
regions.
Arthropod Video
Arthropod Characteristics
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Their jointed feet are
specialized for sensing,
eating, reproducing,
moving and defending.
Arthropods have a
complex digestive system
with two openings and a
closed circulatory system
(blood vessels like us).
http://www.vifishandwildlife.com/Education/FactSheet/Images/Lobster.jpg
Exoskeleton - made of chitin; is a hard covering on the
outside of body which provides both support and protection
Molting – required for an arthropod to grow; shedding of old
exoskeleton
Arthropoda
Subphylum:
Crustaceans
http://www.mbari.org/seminars/2004/fall200
4/shrimp.jpg
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Think crawfish, lobsters, and crabs!
Crustaceans have legs with claws, chewing mouthparts, two pair
of antennae, and two body segments.