What makes up a mussel shell?
The shell is composed of calcium carbonate and protein. The often white shiny layer seen inside the shell is called the nacre, or “mother of pearl.” The outer layer or periostracum is made of protein and serves mainly to protect the shell. Shells have a variety of shapes-round, elongate, oval or tear-drop.
What is the anatomy of a mussel?
Freshwater mussels are members of the Phylum Mollusca, Class Bivalvia, and Order Unionoida. They have soft inner bodies and hard outer shells consisting of two valves, one on the left side and one on the right side. The shells are joined by an elastic ligament that stretches across a hinge at the top (dorsal margin).
What is the shell of a mussel called?
Bivalve shell
A bivalve shell is part of the body, the exoskeleton or shell, of a bivalve mollusk. In life, the shell of this class of mollusks is composed of two hinged parts or valves.
What do mussel shells look like?
In most marine mussels the shell is longer than it is wide, being wedge-shaped or asymmetrical. The external colour of the shell is often dark blue, blackish, or brown, while the interior is silvery and somewhat nacreous.
What’s inside a shell?
Essentials. Shells are made of calcium carbonate, in the mineral form of calcite or aragonite. Animals build their shells by extracting the necessary ingredients—dissolved calcium and bicarbonate—from their environment.
Do all mussels have pearls?
Every mussel, at least in the minds of men, has the potential to contain a pearl. Mussels, like their salt water counterparts, oysters, create pearls.
Where do mussel shells come from?
Marine organisms such as mussels create shells in several stages. They take up the carbonates and calcium in sea water through their tissue and convert them into a substance known as amorphous calcium carbonate (ACC).
Do mussels have a heart?
Just like us, mussels have a heart, kidneys, a stomach, and a mouth! Like fish, mussels also have gills. The gills of mussels help these animals filter water.
What is the oldest part of a mussels shell called?
beak
The beak is the oldest portion of a mussel shell, formed when the animal was very young. the depression or cavity on the inside of each valve beneath the beak.
How are shells born?
As mollusks live their daily lives in the sea, they take in salts and chemicals from the water around them. As they process these materials, they secrete calcium carbonate, which hardens on the outside of their bodies and begins to form a hard outer shell.
How do you tell if a mussel has a pearl?
There are no obvious signs that an oyster, mussel, or clam has a pearl inside. You just have to open it to see; it’s kind of like a guessing game. That being said, larger oysters, mussels, or clams may have pearls because they’ve had a longer time to develop.
Anatomy of Freshwater Mussels. The shells of mussels have three different layers. The outer layer (called the periostracum) is made of organic material that may be yellow, green, brown, or black. The middle layer ( prismatic layer) is made of elongate crystals of calcium carbonate (CaCO 3 ).
What do fossil shells tell us about mussels?
Fossil shells indicate that mussels coexisted with dinosaurs during the Mesozoic era (Age of Dinosaurs) from 65-245 million years ago. Today there are more than 800 species of freshwater mussels and they live on every continent except Antarctica.
Do all mussels have teeth on the shell?
Shells also vary in the presence or absence of sculpturing (ridges or bumps) on the outer surface. Some mussels have interlocking hinge “teeth” (pseudocardinal teeth and lateral teeth) on the inside of the shell to help keep the two valves in proper alignment. Other species are toothless.
How many valves does a mussel have?
Each mussel has two shells�one left valve and one right valve�that protect the soft-bodied animal from predators. The shells of different species vary in size, shape, thickness, and color. Shells also vary in the presence or absence of sculpturing (ridges or bumps) on the outer surface.