Dearolf
BIOL 220
NAME:________________________________________
WORKSHEET #5: CIRCULATORY SYSTEMS (CHAPTER 31)
1. How are sponges and diploblasts able to transport their food, respiratory gases, and
wastes (page 675)?
2. How can flatworms (Phylum Platyhelminthes) survive without a circulatory system
(page 675)?
3. Define a circulatory system (page 675).
4. Define a closed circulatory system, and give an example of a group of organisms that
possess one (pages 675-676).
5. What is an open circulatory system? Give two examples of organisms that possess
one (page 676).
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Dearolf
BIOL 220
NAME:________________________________________
6. Describe the flow of hemolymph through the body of an arthropod, being sure to
use the words arterial system, baffles, heart, hemocoel, ostia, and septa (page 676).
7. Respiratory gas transport is not the function of the circulatory system in insects and
many other terrestrial arthropods. Which system is responsible for gas transport in
these organisms (page 676)?
8. Briefly describe the heart and circulatory system of fish, being sure to use the words
atrium, body organs, bulbus and conus arteriosus, dorsal aorta, gills, sinus venosus,
and ventricle (pages 677).
9. Diagram, using words, the flow of blood through a mammal heart. Begin with blood
returning to the heart from the body. Through which vessels does it arrive at the
heart, and into which chamber of the heart does it enter? Through which valve does
it pass and into which chamber does it go? From this chamber, through which valve
does it pass and into which structure does it go? This structure takes the blood to
the lungs to be oxygenated. Through which structure does the blood flow to return
to the heart from the lungs? Into which chamber of the heart does it enter?
Through which valve does it pass and into which chamber does it go? Finally,
through which valve does it pass, and into which structure does the blood enter to
take oxygenated blood to the body (page 678).
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Dearolf
BIOL 220
NAME:________________________________________
10. On the cladogram below, indicate whether or not the included phyla exhibit a
circulatory system, and if they possess a circulatory system, indicate if it is OPEN or
CLOSED.
DUE AT THE BEGINNING OF LECTURE ON FRIDAY, OCTOBER 9TH!!
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