Arthropod Exploration

Arthropod Dissection Vu-PAPBIO-3

Crayfish (Astacoidea)

The crayfish (Astacoidea) is an arthropod which belongs to subphylum Crustacea. The crayfish lives in running fresh water such as brooks and streams. The crayfish breathe through feather-like gills that are found on the sides of the crayfish. Crayfish are vulnerable to polluted water so clean water is vital for survival. The crayfish feed off of small living animals such as plankton, plants, and dead animals.

Grasshopper (Caelifera)

The grasshopper (Caelifera) is an arthropod that belongs to class Insecta. The grasshopper lives in a variety of habitats such as tropical wet forests. Grasshoppers have short antennae, which helps the grasshopper have a good sense of thier surroundings, wings, even though the grasshopper can't necessarily fly, and a three part body (head, thorax, abdomen) . The grasshopper can use their hind legs in order to jump great heights and distances. Grasshoppers and herbivores which typically eats grass, weeds, and plants. The grasshopper can make a distinct noise by rubbing the hind femurs against the abdomen or forewings.

Today's objectives.

The students will observe two types of arthropods, a crayfish and a grasshopper, which are both preserved. During observing the student will look for similarities and differences in the traits of both animals.

Arthropod Dissecton

Body System Highlight: Respiratory (Grasshopper)

The exchange of gasses begin at the spiracles where the air is taken in first. Then the exchange goes through the tracheal system. The tracheal system contains 10 spiracles which are located in the abdominal area. Two are thoractic and 8 are abdominal. The air sacks which the tracheal system works with stores carbon dioxide and oxygen when respiration is taking place. Organs that functon within the respiratory system include air sacks, tracheole, spiracle,and tracheae.

Body System Highlight: Circulatory (crayfish)

The crayfish incorporate thier gills in order to breath. The gills of the crayfish are located on the sides of the crayfish between the body wall and the carapace which means the gills are located on the outside. The gills are attached to the leg of the crayfish so when the crayfish walks, the crayfish can breath. The surface area that the gills create allows for contact between blood and the water. This is so the Oxygen from the water can easily diffuse into the blood of the crayfish. This shows that the crayfish can extract oxygen from the water they breathe just like humans can extract oxygen from the air we breathe.