1. Phylum Echinodermata
Characteristics of Echinoderms:
Echinodermata are so named owing to their spiny skin (from the Greek “echinos” meaning
“spiny” and “dermos” meaning “skin”), and this phylum is a collection of about 7,000 described living
species. Echinodermata are exclusively marine organisms. Sea stars, sea cucumbers, sea urchins, sand
dollars, and brittle stars are all examples of echinoderms. To date, no freshwater or terrestrial
echinoderms are known.
Sea Star Sea Urchin
Sea Cucumber Sand Dollars
All echinoderms share the characteristic of radial symmetry, which means their limbs or
appendages all grow out from one identical centreal point.
Importance of Echinoderm
Economical Importance:
Echinoderms are economically important to humans due to their use in scientific
research and education and also for food. Scientists have learned much about animal reproduction,
fertilization and development by studying sea urchins, sea stars and other echinoderms. Scientists have
used echinoderms to study fertilization due to the fact that many
2. species are easy to cultivate in a lab setting and also because they produce a huge amount of eggs at
one time. Echinoderm eggs are also the reason these animals are economically important for food, as
sea urchin roe is considered a delicacy in many places and is commonly served in sushi restaurants
around the world. Echinoderms are a family (or phylum) of sea life that includes sea-urchins, starfish
and sea-cucumbers. They are fished for food in the Far East and South-East Asia, and also have some
use in agriculture and scientific research, and in the making of fish meal.
Echinoderms in Farming:
The hard skeleton of echinoderms is used as a source of lime by farmers in some areas where
limestone is unavailable. Lime is added to the soil to allow plants to take up more nutrients. About
4,000 tons of the animals are used each year for this purpose.
Echinoderms as Medicine:
Echinoderms are also used as medicine and in scientific research. For example, some sea
cucumber toxins slow down the growth rate of tumor cells, so there is an interest in using these in
cancer research.
Sea urchins are also model organisms used in developmental biology research. Sea urchins have been
used to study the mechanisms of fertilization and egg activation, physiological processes that occur
during early development, and the regulation of differentiation in the early embryo. In addition, the
molecular basis of early development was studied in sea urchins. Gametes can be obtained easily,
sterility is not required, and the eggs and early embryos of many commonly used species are
beautifully transparent. In addition, the early development of sea urchin embryos is a highly conserved
process. When a batch of eggs is fertilized, all of the resulting embryos typically develop at the same
time. This makes biochemical and molecular studies of early embryos possible in the sea urchin, and
has led to a number of major discoveries.
Echinoderms as Food
In some countries, echinoderms are considered delicacies. Around 50,000 tons of sea urchins
are captured each year for food. They are consumed mostly in Japan, Peru, Spain and France. Both
male and female gonads of sea urchins are also consumed. The taste is described as soft and melting,
like a mixture of seafood and fruit. Sea cucumbers are considered a delicacy in some south-eastern
Asian countries. In China they are used as a basis for gelatinous soups and stews.
Take an action as a water filter:
All echinoderms actually have no blood. To replace blood, they have this water vascular
system in their body. Just like blood, this system is helping echinoderms to do things with their body
such as to absorb food, transportation inside the body, respiration, and etc. Through this system too, the
ocean water that is coming into their body can be filtered and turn out to be a clearer ocean water.
Spread of disease prevention:
Most echinoderms is known as an omnivore where they feed on almost everything. This may
be a plus point from echinoderms. It will usually eat the dirt in the ocean as well as sick
3. fish. By doing this echinoderm can actually prevent the spread of the disease that may come out from
the sick fish.
Ocean habitat maintainer:
Habitat is a home to a living being. To make you comfortable with a place you are living in
somehow you need to maintain the cleanliness and any other thing that make a habitat stay like what it
is. The existence of echinoderms somehow can help the habitat in the ocean to stay like what it is.
Ocean floor cleaner:
There are a lot of echinoderms species in the ocean. And the existence of echinoderms can be found in
nearly every depth of the ocean. It is classified as an omnivore and by eating the dirt in the ocean floor
it cleaning up the ocean floor and make it clearer. Clearer ocean ecosystem will be able to help the
living being within the ecosystem to live better and comfortably.
Coral reef maintainer:
Since echinoderms is known as herbivore and feeds on almost everything including the dirt,
echinoderms can clean up the ocean ecosystem somehow. Coral reef is one of the ecosystems that need
a specific standard of clear and stable ecosystem. Echinoderms that has a role to clean the ecosystem
can maintain the clear ecosystem for the coral reef to live and grow. This will also prevent coral reef
from bleaching.