Question

Please state what organism these parts are found on / in and if it is external or internal anatomy.

a. pedipalps

b. siphon

c. swimmerets

d. thorax

e. swim bladder

f. tibiofibula

Answer 1

a)Pedipalps (shortened as palps),seen in chelicerates(an arthropod group consisting of spiders,scorpion,crabs,etc.. ) are their second pair of appendages. These are lateral to the jaws and anterior to first pair of walking legs.It is an external organ attached to cephalothorax of the organism.

b)Siphon is a part of the body of aquatic molluscs in three classes like Gastropoda, Bivalvia and Cephalopoda (freshwater snails, octopus, squid).These are tube-like structures in which water flows (for purposes such as locomotion, feeding, respiration, and reproduction). It is part of the mantle of the mollusc.It represents internal anatomy,which is a flap of the mantle that is rolled into the shape of a tube.

C)Swimmerets(Pleopods) are found in crustaceans like prawns,lobsters,crabs etc...It is one of a number of abdominal limbs or appendages, adapted for swimming and for carrying eggs(except in prawns) Swimmerets are external organs found on the first five abdominal segments and typically terminate in paired oarlike branches.

D)Thorax is found in in tetrapods (reptiles,amphibians,mammals).In mammals, the thorax is the region of the body formed by sternum, thoracic vertebrae, and ribs. It extends from the neck to the diaphragm, and heart and lungs reside in the thoracic cavity. It is an external anatomical structure and is the is the chest region of the body between the neck and the abdomen.

E)Swim bladder is a gas filled organ found in fishes.It functions as a hydrostatic organ, enabling the fish to maintain its depth without floating upward or sinking.It is an internal organ located in the body cavity and derived from an outpocketing of the digestive tube.

F)Tibiofibula is the single Shinebone found in mainly Frogs and Toads which helps frog in leaping and thus producing jumps.(tibiofibular joints are found in mammals which refers to two articulations between the tibia and fibula of the leg and play a greater role in stability and weight-bearing).It is an internal anatomical organ which is located between the femur and the tarsus, the tibia and the fibula fuse to form one long bone.