ENT378 Study Guide - Final Guide: Circulatory System, Blood Cell, Adipocyte

• School: University of Alberta
• Department: Entomology (Biological Sciences)
• Course: ENT378
• Professor: Andrew Keddie

Document Summary

Insects have what is called an open circulatory system which is a heamocoel (body cavity) filled with organs and blood (hemolymph). Insects do not have veins or capillaries and very few arteries, blood baths organs that are floating. Note: organs are not freely floating but localized within the body. Specific receptors on the organ help pick up molecules required by the organ. Contains variable number of cells (60-70 types). Hemocytes (categorized by structure/function): prohemocytes: progenitor cells (undifferentiated)-divides to produce 2 cells: another to replace itself and one to differentiate into a specific hemocyte, heamocytopoetic tissue: produces blood cells, triggered under stress can produce mass blood cells. Not localized but closer to dorsal vessel (: therefore two sources of new blood cells are found in insects: prohemocytes and haemocytopoetic tissue, adipocyte: blood cell that stores lots of fat. Since blood is highly aqueous [water], lipids are not mobile in the heamocoel and adipocytes act as a transporter.