All Jharkhand Competitive Exam JSSC, JPSC, Current Affairs, SSC CGL, K-12, NEET-Medical (Botany+Zoology), CSIR-NET(Life Science)

Wednesday, September 30, 2020

Phylum Mollusca - NEET-Biology

 Phylum Mollusca

Fig: Apple snail (Pila)
Characteristics:

  • Mollusca is the second-largest animal phylum & includes snails, slugs, oysters, cuttlefish, octopuses, and many other familiar animals.
  • Bilaterally symmetrical, triploblastic & coelomate animals.
  • The body is covered by a calcareous shell and is unsegmented with a distinct head, muscular foot & visceral hump.
  • Except for cephalopods, all mollusks have such as open circulatory system.
  • Nitrogenous wastes are removed from the body by the nephridium.
  • Mostly dioecious.
  • Fertilization is both external & internal, oviparous with indirect development.
  • Embryo developed into a free-swimming larva called a trochophore.
  • Examples: Pila (Apple snail), Pinctada (Pearl oyster), Sepia (Cuttlefish), Loligo (Squid), Octopus (Devilfish), Aplysia, Dentalium (Tusk shell), Chaetopleura (Chiton)
Fig: Octopus (Devilfish)



Share:

0 comments:

Post a Comment

Unordered List

Search This Blog

Powered by Blogger.

About Me

My photo
Education Marks Proper Humanity.

Text Widget

Featured Posts

Popular Posts

Blog Archive