<p> Name: ______Date: ______Unit 6 Notes #4 – ______CRUSTACEA : The Crayfish</p><p>A) Crustacea: - Crustaceans are primarily aquatic and range in size from the microscopic to the rather enormous (giant spider crab 5-6 meters)</p><p>- Common characteristics include ______exoskeleton, two </p><p>______and feeding mouthparts called ______</p><p>CRAYFISH B) ______Anatomy: -They inhabit freshwater streams and lakes.</p><p>-The thirteen segments in the ______to form the “______”</p><p>-The ______of the skeleton covering the anterior portion of the body is called the “______”</p><p>-Six most posterior segments form the______. Except for the </p><p>Last of these segments, each of these bears a pair of ______. The pair on the ______is important in determining the sex of the crayfish, this pair is ______</p><p>- Each pair of appendages (______) below the Carapace is slightly adapted or specialized to______. B) ______Anatomy: i)______: -Crayfish feed on insect larvae, worms, smaller crustaceans, small snails, fish and tadpoles. -After food is crushed and shredded by their mouth parts, it is passed into the </p><p>______</p><p>______</p><p>-A pair of ______just posterior to the stomach secretes enzymes into the ______. Then digested food passes down the intestine for absorption into the blood.</p><p>-Finally, undigested food passes out through the anus. The anus is found just under the______( ______</p><p>______)</p><p> ii) ______Systems</p><p>-Nervous system is much like that of the ______(ex – Earthworm) with a larger ______located just above the ______</p><p>-It connects to a pair of nerve cords (that appears as a single nerve cord) these nerve cords ______along the body to the______</p><p>-The brain is also connected to the ______</p><p>______-Each ______eye is supported at the end of a moveable stalk. </p><p>-______sensitive to touch are distributed over the body and appendages. ______</p><p>______</p><p>______</p><p>-At the base of the ______are______, which serve the sense of ______</p><p>-Antennules appear on the second segment of the head. These are organs of balance and hearing and touch. </p>