3) Write any two characteristics of above phylum starfish
please tell me the answer
Answers
Answer:
1. These are multicellular organisms with well-developed organ systems.
They have a star-like appearance and are spherical or elongated.
They are exclusively marine animals.
The organisms are spiny-skinned.
They exhibit organ level of organization.
They are triploblastic and have a coelomic cavity.
The skeleton is made up of calcium carbonate.
They have an open circulatory system.
They respire through gills or cloacal respiratory tree.
They have a simple radial nervous system and the excretory system are absent.
The body is unsegmented with no distinct head. The mouth is present on the ventral side while the anus is on the dorsal side.
The tube feet aids in locomotion.
They reproduce sexually through gametic fusion and asexually through regeneration. Fertilization is external.
The development is indirect.
They possess the power of regeneration.
They have poorly developed sense organs. These include chemoreceptors, tactile organs, terminal tentacles, etc.
the body surface is covered with calcareous spicules. body cavity has the distinguishing water vascular system. tube feet help in logomotion. the brain is absent but in our system is present within the range and radial nerve cords.
Please Make me as Brainleast plz plz