Effect of Temperature on the Heartbeat of Daphnia
Daphnia, the water flea, is a crustacean commonly found in fresh water. It is an important herbivore and feeds on algae and is in turn a common food item for many higher trophic levels including fish. Thus, this organism is an important link in the aquatic food chain. Daphnia is small and transparent, making its internal anatomy easy to view. As a result, one can study a number of environmental effects upon the action of the heartbeat of Daphnia. It is also a useful organism for studying the effects of drugs on the heart.
Click to view an image of Daphnia
Consider the following questions:
Class
Arachnida
(Cambell 6th Ed. 664-666; 7th Ed. 658-659)
This group includes such well known organisms as the spiders, ticks, mites and scorpions. Adults are characterized by having four pairs of walking legs.
Ticks are of considerable economic importance because they transmit diseases such as tick paralysis, rocky mountain spotted fever and tularemia. They may also cause problems due to infections and in the case of animals, anemia due to blood loss. Despite these problems, ticks in Manitoba do not present a serious hazard in humans. For more information on ticks, see the article by Dr. T. A. Dick in Manitoba Nature 20:22-30 (1979).
Examine the preserved tarantula from your lab.
