2. INTRODUCTION
Electrogenesis refers to the production of electrical
impulses in the tissues of a living organism.
Observed in all animals such as fishes, reptiles, and
mammals etc.
3. TYPES OY ELECTRIC FISHES
Strongly electric fishes
Example: Torpedo, Electrophorus etc.
Weakly electric fishes
Example: Raja, Gymnotus etc.
RajaElectrophorus
4. Electric organs are organs specialized for the production of
an electric field outside the body.
Built up from a large number of disc like cells, called
electroplates.
Electroplates embedded
in a jelly like extracellular
material and enclosed
within a compartment
of connective tissue.
Diagram showing electric organs
ELECTRIC ORGANS
5. DISTRIBUTION OF ELECTRIC ORGANS
Name of fishes Shape of electric organ Location of electric
organ
Torpedo Flat kidney shape On either side of mid-line
Malapterurus Lozenge-shape Located in skin
Raja (String ray) Spindle-shape Lying parallel to the
spinal cord in the tail
Torpedo Raja
6. PATTERNS OF ELECTRIC ORGAN DISCHARGES
Monophasic pulses
Biphasic pulses
Polyphasic pulses
7. KINDS OF ELECTRIC ORGAN DISCHARGE
Electrophorus: one small pulse followed by four large
pulse.
Electric shark: repetition of sequence of events.
Torpedo: four large pulses which are continuously
repeated.
10. FUNCTION OF ELECTRIC ORGAN
Food procurement
Defense
Species and sex recognition
Direction finding
Communication
Navigation
11. WHY ARE FISHES IMMUNE TO THEIR
OWN ELECTRIC CURRENT ?
Got myolated nerve fibers with high degree of
insulation.
Excitatory muscle fibers have high threshold of
excitation.