CRAYFISH DISSECTION
Image from: http://www.mackers.com/crayfish/
ARTHROPODA
“Arthro” =
“pod” =
joint
foot
“jointed foot”
NAMING CRAYFISHKingdom: Phylum:
CLASS:
ANIMALIA
Arthropoda“jointed foot”
CRUSTACEA
crusta = “flexible shell”
SEGMENTED BODY
TAGMA- pl TAGMATAFusion of smaller segments to make
one bigger section
Head + thorax = cephalothorax
EXOSKELETON- (flexible)made of CHITIN (polysaccharide)PROTEINS, LIPIDS, CALCIUM CARBONATE
http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html
CARAPACE
Section of exoskeleton covering cephalothorax
Image from:
http://rcs.rome.ga.us/hargett/biology/arthpod/craydia.htm
CHELIPED
ROSTRUM
http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html
COMPOUND EYE
Antennae
Antennules
ANTENNAE- touch, taste
ANTENNULES- touch, taste, & EQUILIBRIUM
DECAPODS (10 legs) (4 pair walking legs + 2 chelipeds)
http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html
SWIMMERETS (5 pair)
Telson
Uropods
Image from:http://www.spc.cc.tx.us/biology/jmckinney/Studyimages/crayfish/crayfishdissectlist.html
MANDIBLE
http://www.flushing.k12.mi.us/srhigh/tippettl/biology/cray/mandible.html
Mouthparts Mandible MaxillaMaxillipeds (3 pairs)
Image from:http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html
Appendages1. Walking legs 2. Cheliped 3. Maxillipeds4. 2nd maxilla
(gill bailer)5. 1st maxilla6. Mandible7. Antenna8. Antennule
http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html
APPENDAGESANTENNA Touch, taste
ANTENNULE Touch, taste, equilibrium
MANDIBLE Chew food
MAXILLA Manipulate food Last pair “bailers”- Move water over gills
MAXILLIPEDS Touch, taste, manipulate food
CHELIPED Capture food, defense
WALKING LEGS Locomotion, move water over gills
SWIMMERETS Move water over EGGS, transfer sperm (males) carry young/eggs (females)
UROPOD Propulsion during tailflips
Is it a MALE OR FEMALE? MALES:
first two pair of swimmerets form a channel to transfer sperm to female seminal receptacle
Image from: http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html
SEMINAL RECEPTACLE & SWIMMERETS
Image from:
http://bioweb.uwlax.edu/zoolab/Table_of_Contents/Lab-7b/Crayfish_Sexes/crayfish_sexes.hm
Females “in berry”carry developing embryos on swimmerets
http://crayfish.byu.edu/crayfish_biology.htm
REPRODUCTIVE
SEPARATE SEXES
Male and Female
EXTERNAL FERTILIZATION
sperm & eggs join outside body
INDIRECT DEVELOPMENT
Starts as a LARVA
INDIRECT DEVELOPMENT
MOLLUSKS ECHINODERMS CRUSTACEANS
TROCHOPHORE BIPINNARIA NAUPLIUS Trochophore image: http://www.okc.cc.ok.us/biologylabs/Documents/Evolution/Trochophore_larva.htmNauplius image: http://www.micrographia.com/specbiol/crustac/copepo/cope0100/cycnaup1.htmBipinnaria image:
Examine the inside of your crayfish
GILLS
http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html
RESPIRATORY
Exchange gasesremove nitrogen waste (AMMONIA)
Image from: http://faculty.clintoncc.suny.edu/faculty/Michael.Gregory/files/Bio%20102/Bio%20102%20Laboratory/ Protostomes/protostomes.htm
GILLS are attached to base of walking legs.
Last pair of maxilla = “bailers” & walking move water over gills
Image from: http://www.aa.psu.edu/div/mns/biology/crayfish/crayfishtable.htm
GAS EXCHANGE IN GILLS
INTERNAL
http://www.aa.psu.edu/div/mns/biology/crayfish/crayfishtable.htm
http://www.aa.psu.edu/div/mns/biology/crayfish/crayfishtable.htm
CIRCULATORY
Image from:
http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html
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
Movie from: http://www.gsu.edu/~bioasx/heartbeat.html
PYLORIC
CARDIAC
GASTRIC MILL“teeth” inside stomach
3. DIGESTIVE GLAND 4. ADDUCTOR muscles move mouthparts 5. STOMACH
Image from:
http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html
DIGESTIVE
ABDOMEN
Image from:
http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html
2. Heart 3. Digestive (hepatopancreas) gland. 4. adductor muscle 5. stomach
Image from:
http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html
GREEN GLANDS collect and remove nitrogen waste (AMMONIA) and excess water
Image from:
http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html
NERVOUS
Image modified from:
http://www.student.loretto.org/zoology/Graphic%20webs/Crayfish%20nervous%20system.htm
VENRAL NERVE CORDCEREBRAL GANGLIAGANGLIA along body
NERVOUS
Pair of nerves lead from the ventral nerve cord around the esophagus to the large ganglion, or brain, in the head.
Short nerves connect the eyes, antennae, and antennules to the brain.
http://www.flushing.k12.mi.us/srhigh/tippettl/biology/cray/ganganterior.html
COMPOUND EYE
Thousands of SENSORY HAIRS project from exoskeleton over entire body sense vibrations & chemicals
http://biog-101-104.bio.cornell.edu/BioG101_104/tutorials/animals/crayfish.html