Crayfish Dissection

Crayfish Dissection 

-Crayfish live in almost all bodies of freshwater. They can survive in ponds, lakes, streams, rivers, and sometimes even water-filled ditches.

-They get their nutrition from both animals and plants, making them omnivorous. They eat both living and dead organisms, as long as they are relatively fresh. Some food they eat includes worms, insect larvae, frogs, salamanders, toads, insects, and fish eggs.

-Crayfish breathe through their gills which are located on both sides of their cephalothorax. Their gills are protected under their exoskeletons. Once passed through their gills, oxygen passes and diffuses into their bloodstream. Carbon dioxide leaves through the gills and is passed into the water.

-Red colored crayfish are the most common, followed by blue colored crayfish, and least commonly white crayfish.

Sources-

http://www.fcps.edu/islandcreekes/ecology/crayfish_%28cambarus%29.htm

http://www.ehow.com/info_10016579_crayfish-oxygen.html

http://www.johnston.k12.ia.us/schools/lawson/gradelevellinks/crayfish/funfact.html

Dissection

Major internal/external anatomy-

 

third maxilliped- used to manipulate food

 

walking legs- used for movement and is attached to gills

 

swimmerets- used for movement and determining sex

 

 

Major internal/external anatomy-

 

telson/uropod- used in rapid, backwards escape swimming

 

abdomen- segmented and flexible for easy movement

 

thorax- makes up the cephalothorax

 

cervical groove- separates the head and thoracic regions

 

head- makes up the cephalothorax

 

cephalothorax- used as an armor/ protection

 

compound eye- allows the crayfish to see and detect movement

 

cheliped- claws to grab onto things and defense against predators

 

antenna- used as sensory feelers for touch, taste, and equilibrium

 

 

Major internal/external anatomy-

 

stomach- breaks down food; it’s the first site of chemical digestion

 

gills- water and oxygen exchange

 

heart- pumps blood throughout the crayfish’s body

 

Major internal/external anatomy-

intestine- the small intestine absorbs nutrients from food and the large intestine collects waste and absorbs water

 

tail muscles- help in strong movement of the crayfish

Anatomy Sources-

http://mrescience.com/images/pdf/pdf_life/crayfish_dissection.pdf

http://biologycorner.com/worksheets/crayfishexternal.html