Transcript CrayfishDisssection

CRAYFISH
DISSECTION
READ ME!
http://evolution.berkeley.edu/evolibrary/article/0_0_0/a
rthropods_conclusion_01
Animal Groups
ARTHROPODA
“jointed foot”
“Arthro” = joint
“pod” = foot
Insect, scorpion, crab, or crayfish...YOU TELL ME! CLICK HERE!
NAMING
Kingdom:
Phylum:
CRAYFISH
ANIMALIA
Arthropoda
“jointed foot”
CLASS: CRUSTACEA
crusta = “flexible shell”
(All Arthropods are invertebrates)
BEFORE WE START
• Let’s Make Some
Rules
• Put on your goggles,
aprons, and gloves.
http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html
EXOSKELETON- Outside body;
Made of CHITIN (polysaccharide)
PROTEINS, LIPIDS, CALCIUM CARBONATE
All animals with an EXOSKELETON
must MOLT (shed their exoskeleton)
to grow bigger).
Click HERE! Molting in Action!
SEGMENTED BODY
like earthworms
Fusion of smaller segments to make
one bigger section
Head + thorax = cephalothorax
CARAPACE
Part of exoskeleton that
covers the cephalothorax
Thousands of SENSORY HAIRS project from
exoskeleton over entire body sense vibrations &
chemicals
CHELIPED = Pincher (defense; capture food)
CLICK HERE! CHELIPEDS IN ACTION
ROSTRUM = “visor” protects eyes
ANTENNAE- touch, taste
ANTENNULES- touch,
taste, & equilibrium
http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html
DECAPODS (10 legs)
Watch me Walk!
(4 pair walking legs + 2 chelipeds)
SWIMMERETS (5 pair)
SWIMMERETS
HELP with
REPRODUCTION and moving
water (oxygen) over gills
Males – transfer sperm
Females – carry eggs/young
CLICK HERE! SWIMMERETS IN ACTION!
Telson
Uropods
For Swimming
Forwards &
Backwards
Crayfish Eyes
• Eyes are on moveable
stalks so they can see
all around them.
QuickTime™ and a
decompressor
are needed to see this picture.
COMPOUND EYE
• Compound eyes
are like many
small eyes in
one.
• They are great at
detecting
movement.
• They DO NOT
see good detail
APPENDAGES
ANTENNA
ANTENNULE
MANDIBLE
Touch, taste
Touch, taste, equilibrium
Chew food
MAXILLA
Manipulate food
Last pair “bailers”Move water over gills
Touch, taste, manipulate food
MAXILLIPEDS
CHELIPED
WALKING LEGS
SWIMMERETS
UROPOD
Capture food, defense
Locomotion,
move water over gills
Move water over EGGS,
transfer sperm (males)
carry young/eggs (females)
Propulsion during tailflips
MANDIBLE
MOUTHPARTS
1. antennules
2. Antennae
3. Mandibles
4. 2nd maxillae
5. 1st maxillipeds
6. 2nd maxillipeds
7. 3rd maxillipeds
8. chelipeds
9. Green glands
opening
http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html
Appendages
1.
2.
3.
4.
5.
6.
7.
8.
Walking legs
Cheliped
Maxillipeds
2nd maxilla
(gill bailer)
1st maxilla
Mandible
Antenna
Antennule
SWIMMERETS
MALES
Top pair
make a
“V”
Male Vs Female
1.
2.
3.
4.
Larger top pairs
of swimmerets
for-transfer
sperm to female
Vas Deferenssperm released
here
Opening to the
oviducts
Seminal Vesicle
on Female
Females “in berry”
carry developing embryos on swimmerets
CLICK HERE! CRAYFISH IN BERRY!
REPRODUCTIVE
SEPARATE SEXES
Male and Female
EXTERNAL FERTILIZATION
sperm & eggs join outside body
INDIRECT DEVELOPMENT
Starts as a LARVA
Cut the carapace
(shell) to see the
inside of your
crayfish
http://www.youtube.com/watch?v=Xs
nptcqZAeQ (Start at 1 minute)
RESPIRATORY
GILLS
Exchange gases.
Filter Oxygen from Water
Remove nitrogen waste (AMMONIA)
WALKING LEGS:
are attached to gills. This helps
crayfish use legs to move more oxygen
rich water past the gills.
INTERNAL
OPEN CIRCULATORY SYSTEM
HEART with openings (OSTIA)
ARTERIES leaving heart but NO VEINS to
return hemolymph
OSTIA
Image from:
http://www.quia.com/jg/265982list.html
ADDUCTOR MUSCLES
run mouthparts
STOMACH
GASTRIC MILL
“teeth” inside stomach
TESTES (MALE)
Females:
OVARIES – make eggs
SEMINAL RECEPTACLES-store received
sperm
ABDOMEN
INTESTINE (4) – finish digestion; absorb nutrients
collect & remove feces
Tail
Muscles (3)-locomotion/movement
http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html
GREEN GLANDS - collect and remove excess
water & nitrogen waste (AMMONIA)
http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html
NERVOUS SYSTEM
like earthworms
VENRAL NERVE CORD
CEREBRAL GANGLIA
GANGLIA along body
VENTRAL NERVE CORD
Image by Riedell/Vanderwal © 2005
CEREBRAL GANGLIA =
BRAIN
Notice the Nerve
cords attached to
the brain. These
connect to the main
ventral nerve cord.
AUTOTOMY &
REGENERATION
Crayfish have
the ability to
“self
amputate”
parts to escape
predators and
regenerate to
repair injuries