Electric organ in Torpedo

1. School of Applied Science, CUTM, BBSR
Presented by- IPSITA SAHOO
Reg. no- 200705180160
Supervised by-
Dr. Yashaswi Nayak
Electric organ in Torpedo

2. Torpedo; Classification, Geographical Distribution
General characteristics of torpedo
Special features of torpedo
Why are fishes immune to their own electric current ?
Functions of electric organ
references
CONTENTS

3. Torpedo
HABIT AND HABITAT
Torpedo or Astrape is a marine carnivorous
fish, found on flat. sandy or maddy bottom at
a depth of 80-100 meters. It is carnivorous
and viviparous producing young ova.
GEOGRAPHICAL DISTRIBUTION
Torpedo has been reported from the
Mediterranean, Atlantic and Indian Oceans,
Red Sea, Pacific Ocean. East Indies,
Tasmania, China, Japan, South Africa, North
and South America as well as Australia.
Torpedo is a genus of rays, commonly known as electric rays, torpedo rays, or torpedoes. They are
slow-moving bottom-dwellers capable of generating electricity as a defense and feeding mechanism.

4.  Commonly known as Electric ray because of the presence
of a pair of electric organs, one either side of the body
between head and the pectoral fins.
 Body is divided into anterior semicircular disk supported
by endoskeleton and posterior tail Fish measures 60 to 90 cm
across the widest part of the disk and the whole body has
brown background which is ornamented with beautiful
irregularly shaped, magenta-coloured spirals and spots.
 Semicircular region is supported by branched prenasal
rostrum and laterally by branched pre-orbital cartilages.
Branches radiate towards periphery.
 Disk is bordered by pectoral fins.
 Skin smooth, non-tuberculate and without scales.
 Mouth is transverse and ventrally situated.
 Tail is thick and short with 1 dorsal fin, 2nd dorsal fin and
caudal fin. Pelvic fins are beneath the lower margin of the
pectoral fin.
General characteristics of torpedo : ELECTRIC RAY
Image source- https://www.faunafondness.com/torpedo-electric-ray/

5.  Torpedo contains a pair of large electric
organs between margins of pectoral fins and
head. These organs are considered as
modifications of the adductor mandibulate and
constrictor muscles and supplied by vagus and
trigeminal nerves from vagus and trigeminal
nerves from electric lobe of the medulla.
 Each electric organ is composed of
hexagonal cells called electroplexes which are
filled with jelly-like fluid and arranged
vertically like prisms between upper and lower
surfaces. Upper surface corresponds to anode
and lower surface with the cathode. Thus,
electric current of 50 to 60 volts passes from
upper positive to lower negative surface. After
fish has discharged electricity, some rest is
required for further discharge. These are
offensive and defensive organs and fishermen
get electric shocks from captured electric rays.
Special features of torpedo : ELECTRIC RAY
Image source- https://www.faunafondness.com/torpedo-electric-ray/

6.  Got myolated nerve fibers with high degree of insulation.
 Excitatory muscle fibers have high threshold of excitation.
Why are fishes immune to their own electric current ?
 Catching food.
 As defense organ.
 As a warning device
 Maintaining territory.
 Species Recognition.
Function of Electric organ

7.  Bray R.N.; Hixon M.A.; 1978; Abstract - Predatory Behavior of
the Pacific Electric Ray (Torpedo californica); Science Vol. 200,
p333-334; - USA
 Farrell, A. P. (2011). Encyclopedia of fish physiology: from
genome to environment. Academic press.
References