Answer:
Environmental factors and climate conditions affect the growth and how fast they grow.
Explanation:
An echinoderm is an organism (all marine) that has a spiny skin. The word "echinoderm" means "spiny skin." Starfish, sea cucumbers, brittle stars, and sea urchins are examples.
Most echinoderms develop from larvae to adolescent echinoderms by direct, or indirect development. In direct development, the fertilized egg is able to enter juvenile stage without becoming a larva. The juveniles stay close to the parent, and are cared for and looked after.
Echinoderms evolved from animals with bilateral symmetry. Although adult echinoderms possess pentaradial, or five-sided, symmetry, echinoderm larvae are ciliated, free-swimming organisms that organize in bilateral symmetry which makes them look like embryonic chordates.
Echinoderms have adapted to match the colour of their surroundings. Also, to protect and structure their bodies, Echinoderms such as sea urchins have interlocking plates of Calcium Carbonate which form a very hard internal skeleton.
