What holds clam shells together?

Bivalve molluscs are completely enclosed by a shell made of two valves hinged at the top. A hinge ligament made of elastic protein joins the two halves of the shell together, and large adductor muscles between the two valves hold them closed.

What holds a clams shell shut?

At the front and rear of the animal are anterior and posterior adductor muscles, The muscle fibers run transversely, across the clam, from shell to shell, and their action is to close shut. Some bivalves have two adductor muscles, like the common clam we use here.

How do clams attach?

Most burrow into the soft substrate to varying depths, while some groups live free on the sea floor. There are also clams and mussels that can attach themselves permanently to the substrate by using special anchoring threads called byssal threads.

What holds two valves together?

hinge ligament
A hinge ligament is a crucial part of the anatomical structure of a bivalve shell, i.e. the shell of a bivalve mollusk. The shell of a bivalve has two valves and these are joined together by the ligament at the dorsal edge of the shell.

What is a by valve?

A bicuspid aortic valve is an aortic valve that has two flaps (cusps) instead of three. It may cause a narrowed or obstructed aortic valve opening (aortic valve stenosis), making it difficult for the heart to pump blood into the body’s main artery (aorta).

What is a clam mantle?

The mantle, a thin membrane surrounding the body of the clam, secretes the shell. The oldest part of the clam shell is the umbo, and it is from the hinge area that the clam extends as it grows.

Where is the valve on a clam?

A mollusc valve is each articulating part of the shell of a mollusc. Each part is known as a valve or in the case of chitons, a “plate”. Members of two classes of molluscs, the Bivalvia (clams) and the Polyplacophora (chitons), have valves.

How do clams make their shells?

Mantle tissue that is located under and in contact with the shell secretes proteins and mineral to form the shell. Think of laying down steel (protein) and pouring concrete (mineral) over it. Thus, seashells grow from the bottom up, or by adding material at the margins.

How do clams open and close their shells?

You might have observed this yourself through the clam’s most iconic activity: opening and closing its shell. Clams close their shells with powerful adductor muscles which pull the two valves together. A springy ligament at the hinge pulls the shell open when the muscles relax.

How and where are the valves of a clam held together?

BACKGROUND: Clams are bivalves, meaning that they have shells consisting of two halves, or valves. The valves are joined at the top, and the adductor muscles on each side hold the shell closed.

What does the mantle of a clam do?

The mantle encloses the mollusk’s visceral mass, which is its internal organs, including the heart, stomach, intestines, and gonads. In mollusks that have shells, such as clams, mussels, and snails, the mantle is what secretes calcium carbonate and a matrix to form the mollusk’s shell.

What do valves do in clams?

Internal structure of a clam. A ligament hinges the shell’s two halves (valves) open, and the beating motion of cilia on the gills causes water to enter through the incurrent siphon. As water moves over the gills, oxygen diffuses into the blood, and food particles become trapped in mucus and are moved to the mouth.