The Life of An Arthropod
Arthropod Lab PreAP Bio Vu
Grasshopper and Crayfish (Caelifera and Astacoidea)
The grasshopper and crayfish are both in the phylum Arthropod. The grasshopper resides in grass and it eats grass, leaves, and crops. The grasshopper's predators include birds, other insects, and humans. The crayfish resides in freshwater and it eats earthworms. The crayfish's predators include fish, turtles, and humans.
Objectives
Students will look for similarities and differences in the grasshopper and Crayfish.
Characteristics of Arthropods
All arthropods have an exoskeleton, jointed legs, compound eyes, and segmented bodies.
External Anatomy of a Grasshopper
The grasshopper is divided in 3 regions: Head, Thorax, and Abdomen.
Preserved Grasshopper
Notice that the grasshopper has 3 pairs of legs, 3 pairs of body regions, wings, and a pair of antennae. The whole grasshopper is encased in a exoskeleton. The big leg that is missing in this picture is used for jumping.
Internal Anatomy of a Grasshopper
External Anatomy of a Crayfish
The crayfish is divided into 2 body segments: Cephalothorax and Abdomen.
Preserved Crayfish
Notice the crayfish has 2 body segments, 5 pairs of legs, a pair of antennae, and it doesn't have wings. The whole thing is encased in an exoskeleton. A crayfish's claws are used to defend itself and attack it prey.
Internal Anatomy of a Crayfish
Integumentary System
Both arthropods (grasshoppers and crayfish) have a tough outer covering called the exoskeleton. The exoskeleton of each animal supports and protects the animals' body. In contrast to an exoskeleton, an exoskeleton is able to fall off an animal in order for the animal to grow.
The integumentary system works closely with the nervous system for the sense of touch. It also works with immune system because it protects the body from disease.
Human Interaction
Grasshoppers are considered as pests in the farming community because they like to eat cereal crops. In some countries, grasshoppers are eaten.
Crayfish are also pests as well. They like to burrow underneath people's lawns which makes mowing hazardous. They are also eaten. Fishermen use crayfish as fish bait.
Additional Info
The phylum Arthropod is the largest phylum. The compose of 90% of the animal kingdom. Grasshoppers have ears on their bellies. Crayfish can be blue, red, or white.
Bibliography
images.google.com
www.johnston.k12.ia.us/schools/Lawson/Gradelevellinks/Crayfish/funfact.html
Lab Packet