4.Write down the main characteristics of phylum Annelida, Arthropoda, Mollusca Echinodermata and Hemichordata with examples.
Answers
Answer:
On a pleasant evening, you decide to go to a park. However, you end up having painful itchy eruptions on the skin. Clearly, you were bitten by an insect. After all, insects are everywhere. They belong to a group of animals called the Phylum Arthropoda, which form the largest percentage of the world’s organisms. They make up about 80 percent of the known species of animals! It is quite hard to escape them.
Answer:
Porifera:
Their body consists numerous pores.
The are mostly marine organisms.
These animals are covered with the hard outside layer.
Their bodies have no symmetry.
Examples - Sycon, Spongilla, Euplectella and Euspongia.
Platyhelminthes:
Body of animal is dorsoventrally flat means from top to bottom.
Male or female sex organs are present in the same animals.
Sexes may be unisexual but mostly are bisexual.
They excrete from special organ called nephridia.
Example = liver flukes, planaria, tapeworm.
Nematoda:
They are bilaterally symmetrical.
These are triploblastic and pseudocoelomates.
Nervous system is ladder like.
Body is unsegmented.
Examples = Ascaris, Ancylostoma, Wuchereria.