Скачать или смотреть Phylum Mollusca | Animal kingdom | Class 11 | NEET Biology | by Dr. Umesh Shukla

Phylum Mollusca | Animal kingdom | Class 11 | NEET Biology | by Dr. Umesh Shukla #neetbiology #neet

Characteristic Features of Phylum Mollusca

-They are bilaterally symmetrical.
-They are triploblastic, which three layers.
-They show organ system grade of organisation.
-The body is soft and unsegmented.
-Body is divisible into three regions – head, a visceral mass, and ventral foot.
-Body is covered by a mantle and shell.
-They can be found in different habitats, both aquatic and terrestrial.
-The body cavity is a haemocoel, through which blood circulates.
-The digestive system is well developed and complex. It has a radula, which is a rasping structure that has chitinous teeth. It is used in feeding.
-The nervous system is made up of paired ganglia, connectives, and nerves.
-The circulatory system is open, with heart and aorta.
-Respiration occurs through gills called ctenidia.
-The ventral muscular foot helps in locomotion.
-They have a pair of kidneys (metanephridia)
-Sexes are separate and reproduction is through sexual reproduction.
-Fertilisation can be internal or external.
Mollusca Examples
Following are a few examples of the animals belonging to phylum Mollusca:

Pila (Apple snail)

Limax (Slug)

Unio (Freshwater mussel)

Turbinella (Shankha)

Helix (Garden snail)

Octopus (Devilfish)

Loligo (Squid)