Fill in the blanks. 1.
live on the blood or tissue of other organisms.
2. The type of teeth seen in are usually broad and flat.
3. Some animals have specialized cells that absorb food, break it down internally, and pass the
nutrients to other cells in a process called
4. have some tissues such as cell walls, which require special structures like rumen to
break down in the digestive system.
5. Gas exchange involves the absorption of into the bloodstream and the release of CO2
waste
6. Aquatic animals have specialized structures called that allow for oxygen to be
absorbed into the bloodstream directly from water as it passes through.
7. Insects typically have circulatory systems.
8. Ammonia must be converted into urea in the to be excreted later in mammals as urine.

1. Parasites

2. herbivores

3. phagocytosis

4. Plant

5. oxygen (O2)

6. gills

7. open

8. urea

9. Single-loop circulatory systems have one direction of blood flow. Typically in fish, oxygen is absorbed in the gills, flows in blood to the body organs, and back to the heart, which pumps it directly back to the gills. In double-loop circulatory systems, the heart has multiples of each chamber. Part of the heart pumps blood to the lungs, to get oxygen. This blood flows back to a different chamber where it then gets pumped to the body. Once its oxygen has been used up, it goes back to the heart to be pumped all over again to the lungs.

10. Freshwater animals have lower water and higher salt concentrations than the environment in their cells. This means water constantly tries to diffuse into the animals, which can bloat them. They have special cell processes that remove extra water.

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