Weakly Electric Fish
For Student Groups
Nerve signals are passed on electrically. But how exactly does a cell function like an electrical circuit? In this course, students learn the basics of neuronal signaling and perform extracellular measurements on a model organism. The course is rounded off by an experiment on behavioral science.
- 16 to 20 years
- 1 day
- Maximum number of participants
- Introduction to the use of an oscilloscope
- Recording of the single signal of weak electric fish
- Reaction of weak electric fish to signals (measurement of signal sequences)
In order to generate signals, a nerve cell must have certain characteristics: It must be able to build up a membrane potential and change it in a controlled manner. This course explains which proteins and processes are important in this context. A model organism is used to measure electrical signals: Weakly electric fish (Gnathonemus petersii) send their signals into the water to orient themselves. However, these signals are generated in a similar way to the action potentials of the nerve cells, so that the students can transfer their knowledge and explain the fish signals. Measurements are taken extracellularly with oscilloscopes, so that the fish can move freely in the aquarium. In the second part of the course, signal sequences instead of single signals are analysed: These sequences change when sensory stimuli are presented to the fish. In order to be able to quantify this change, the data are recorded with a recording program. This program displays the signal sequence over several seconds and enables the students to determine precise signal frequencies at different times. The measurements are performed using a simple recording program.