phylum mollusca pdf notes||NEB||

Are you searching for complete notes of phylum mollusca chapter for class 12..?Here,in this post you will get the complete notes of phylum mollusca chapter for class 12 (NEB NEW COURSE). Trust you will think that it is useful.if you don't get too much trouble, share it with needy ones.

Phylum Mollusca is a large and diverse phylum of invertebrate animals, with over 100,000 species known to science. Molluscs are found in a variety of marine, freshwater, and terrestrial habitats, and they exhibit a wide range of morphological and ecological diversity. Some of the most familiar molluscs include snails, clams, oysters, squid, and octopuses.

Molluscs are characterized by a number of unique features, including a muscular foot used for locomotion, a mantle that secretes a protective shell in most species, and a radula, a specialized feeding structure used to scrape food particles from surfaces. They also possess a well-developed nervous system and complex sensory organs, such as eyes and statocysts for balance.

There are seven major classes of molluscs: Gastropoda, Bivalvia, Cephalopoda, Polyplacophora, Monoplacophora, Scaphopoda, and Aplacophora. Each class is defined by specific morphological and physiological characteristics.

Gastropoda, the largest class of molluscs, includes snails and slugs. They are characterized by their single, spirally coiled shell or the absence of a shell in some species. They move using a muscular foot that is typically located on the ventral side of the body. Many gastropods are herbivores, feeding on algae or plant material, while others are carnivores or scavengers.

Bivalvia, also known as pelecypods, includes clams, oysters, and mussels. They have a two-part hinged shell that encloses the soft body, and they are sessile filter feeders, using specialized gills to capture food particles from the surrounding water. Bivalves are important members of marine and freshwater ecosystems, and they are also commercially harvested for food.

Cephalopoda, which includes octopuses, squid, and cuttlefish, are the most advanced and intelligent of the molluscs. They have a well-developed nervous system and complex sensory organs, including large eyes that are similar in structure to those of vertebrates. They also possess a unique method of locomotion, using a jet propulsion system powered by water expelled from the mantle cavity. Cephalopods are active predators, using their tentacles and beak to capture and eat prey.

Polyplacophora, also known as chitons, are small, flattened molluscs that are covered with overlapping shell plates. They have a broad muscular foot that allows them to cling to rocks and other hard surfaces in the intertidal zone. Polyplacophorans are herbivores, using their radula to scrape algae from the substrate.

Monoplacophora, a small and ancient class of molluscs, was thought to be extinct until a living species was discovered in the 1950s. They have a single, flattened shell and a segmented body, and they are found only in deep-sea environments.

Scaphopoda, or tusk shells, are elongated, cylindrical molluscs that live buried in sediment. They have a conical, tubular shell that is open at both ends, and they use a muscular foot to move through the sediment and capture food particles.

Aplacophora, or worm-like molluscs, are a small and poorly understood class of molluscs. They lack a shell and have a worm-like appearance, and they are found primarily in deep-sea environments.

Molluscs play important roles in ecological systems, serving as prey for a variety of predators, and in turn, acting as predators of smaller organisms. They also play important roles in nutrient cycling and in

Here,you will get complete notes of phylum mollusca chapter for class 12 in pdf design and you can download pdf of phylum mollusca chapter by using download button beneath:

File Name: phylum mollusca full pdf notes for class 12 Uploaded By: Sumit RajakFile Size: 1.8Mb