Using Caffeine to Hyperactivate Bull Semen

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Using Caffeine to Hyperactivate Bull Semen
A Lab Exercise in Reproduction and Development

Available from NABT by Clicking here

Authors
Paula Jones
Wayne Gottlieb
Susan S. Suarez

WHBR is not an official distributor of this activity; although we can supply bull semen and are really excited about this activity. To support its use we provide the abstract (below), a link to an NABT site where the activity can be downloaded (above), the following videos, and a link to our catalog where interested teachers can order bull semen for use with this lab.


Clip discusses and demonstrates materials and techniques used in the lab.	Clip shows unstimulated sperm exhibiting progressive motility.	Clip shows hyperactivated sperm. Note that the tail beating is asymmetrical, which drives the sperm in circles on a microscope slide.

Abstract
The introduction of reproduction utilizing only the usual array of textbook graphs and diagrams can take an otherwise fascinating subject, particularly to high school and college-age students, and reduce it to sheer boredom. This exercise gives students the opportunity to see live, swimming mammalian sperm and to watch how they respond to a trigger that prepares them for fertilization in the same way that they are prepared to fertilize eggs inside the female. The trigger we use in this experiment is caffeine, a chemical familiar to students. While it is not the physiological trigger (which is unknown at present), it produces the same effect. Although students are taught that cells respond in many ways to different molecules, they rarely get a chance to observe these responses or to see how cells might respond to a chemical that is familiar to them. Here is a chance to actually see a cell respond to something that a student might drink every day. This exercise will reinforce students' understanding of mammalian reproductive processes by enabling students to see live sperm. In addition, the use of caffeine to produce a change in sperm that is normally undergone just before fertilization can foster an interesting discussion about how caffeine might affect sperm in the men and women who drink it, including a discussion of how caffeine could get from the digestive tract to the reproductive tract via the circulatory system. This experiment includes controls that show the importance of using proper controls in designing experiments.

Appropriate Levels
Life Science, Biology, Honors, AP, and Tech prep, depending upon the level of discussion and types of questions asked.

Time Required
Assembling the various reagents necessary will require about an hour of prep time before the class. In class, the activity can be completed in one 50 minute period.

Materials

Please consult the lab by visiting the NABT site listed above for detailed list of reagents required.

Bull Semen can be order from WHBR as item# RD-501