Do You Know? Shellfish

Shellfish are aquatic animals that include soft-bodied animals (molluscs).

Shells are common sense and has no biological significance but its use is widespread and used in economic activity.

In the broadest sense, means all mollusc shells with a pair of shells (see bivalves). With this understanding, more precisely people call shellfish and clam commensurate with the meaning used in America. Examples of such usage can be seen on the term "craft of shells."

• The word can also mean any bivalve shellfish that lives attached to an object. Into it, including the types that can be eaten, such as blood clams and green mussels (kupang awung), but not including the types that can be eaten but sprawled on the sand or water base, such as the seashell and mussels.
• Shells are also used to refer to a variety of shellfish are thick shelled, calcareous, with a radial pattern on the shell firmly. In this sense, green shells are not included in it and is more appropriately called kupang. Understanding the closest in English is Cockle.
• In the narrowest sense, which is referred to as the shells are blood clam (Anadara granosa), a type of shellfish cultivation which are common in the Indo-Pacific region and many are sold in shops or restaurants that sell seafood.

Common characteristics
All shellfish has a pair of shells (also called graft or valve) is usually a mirror symmetry that is connected by a ligament (connective tissue). In most shells there are two adductor muscles that govern open-shell lid.

Shellfish do not have a head (also the brain) and only simping who have eyes. Organ which is owned by the kidneys, heart, mouth and anus. Shellfish can move with "legs" of such a flat organ that issued from the shell at any time or by opening and closing their shells as a surprise.

Open circulation system, meaning no blood vessels. The supply of oxygen from the blood of a very liquid rich in nutrients and oxygen that surrounds the organs.

Shellfish food is plankton, by filtering. Shellfish themselves are prey for squid and shark.

All shellfish is when a young male. Some females will be in line with the maturity.