Crayfish Lab Preview April 24, 2012

 Crayfish General Information:  Phylum: Arthropods - means “jointed foot”  Class: Crustaceans  2 Body Parts:  Cephalothorax  Abdomen  Review: General Terms:  Dorsal – top side  Ventral – bottom side  Anterior – front end  Posterior – back end Anterior Ventral Dorsal Posterior Cephalothorax Abdomen

 Crayfish External Features: Antennae Cheliped Telson Segment Walking legs Compound Eye

 Crayfish Body Systems  Circulatory System – How the blood circulates through the body.  Dyed pink  Heart - pumps blood.  Arteries – transports blood into open spaces (open circ. System)  Respiratory System  Gills – breathe under water. Heart Dorsal Abdominal Artery Ventral Abdominal Artery Gills

 Crayfish Body Systems Continued  Nervous System – Used to sense and feel things  Brain – very difficult to see.  Nerve Cord – only on ventral side of the crayfish Brain Nerve Cord

 Crayfish Body Systems Continued  Reproductive System – Making more crayfish  Male – letter A in picture  Testis – make sperm  Sperm Duct  Male opening  Swimmerets – moves sperm  Female – letter B in picture  Ovary – holds eggs  Oviduct opening  Swimmerets – moves eggs Testis Sperm Duct Swimmerets Ovary Oviduct opening

 Crayfish Body Systems Continued  Digestive System – Taking in food and breaking it down.  Mouth  Esophagus  Stomach - 2 interesting features  Location  Rows of teeth  Intestine  Anus Stomach Intestine Anus Mouth Esophagus

 Crayfish Body Systems Continued  Excretory System – Gets rid of wastes.  Anus – releases wastes. Anus