1. Comparative Circulatory Systems Biology 11 G.Burgess 2006

2. Circulatory Systems Nutrients, fluids and metabolic wastes are cycled through an organism’s circulatory system Microscopic animal like protists and the least evolved animal species use cyclosis and diffusion to cycle their materials through cells and between cells. Plants use xylem and phloem to circulate materials between the roots, stems and leaves. Animals (more complex than the cnidarians/jelly fish) use either an open or closed circulatory system

3. Open circulatory system Common among shellfish and arthropods (arachnids and insects) Heart collects blood from a hemocoel (blood space) Heart pumps blood through open ducts or tubes to be circulated to the body tissues and bathe them with fluids. Cycled blood collects in hemocoel to be collected by the heart

4. Closed Circulatory System Common among annelids, fish, mammals and many other animals All blood vessels form a continuous closed circuit Blood is collected by atria and pumped to body by ventricles At no time does the blood actually come in contact with other body tissues.

5. Earthworm Circulation Closed circulatory system –Blood from the dorsal blood vessel travels to the anterior region and is pumped by 5 aortic arches to the ventral blood vessel –Blood from the ventral blood vessel travels posteriorly –Small tubes connect the ventral blood vessel to the dorsal blood vessel in the posterior region.

6. Earthworm Circulatory system Dorsal Blood Flow Ventral Blood Flow

7. Grasshopper Circulation Grasshoppers have open circulatory system Their blood bathes their internal tissues Grasshopper do not have hemoglobin, their blood is green and is called hemocyanin

8. Grasshopper Circulatory System

9. Other animals FishFrog Human

10. Mammalian Circulation All mammals have a 4 chambered heart 2 Atria and 2 ventricles The atria collect blood from the circulatory system and pump it to the ventricles The ventricles pump the blood to parts of the body 2 paths of circulation: –Systemic circulation: pumps blood to and from body tissues –Pulmonary circulation pumps blood to and from the lungs

11. Bibliography All images from Biodidac, 2006. http://biodidac.bio.uottawa.ca/