2006-10-29 02:52:13 · 6 answers · asked by Curious 1 in Environment
all shells were once living creatures....probably the same as your finger and toe nails
2006-10-29 02:53:46 · answer #1 · answered by Anonymous · 0⤊ 1⤋
Seashells are, quite simply, the exoskeletons of mollusks. At Britannica.com, we learned a good deal about the composition of seashells, including the three distinct substances involved: an outer layer of the horny substance conchiolin, an intermediate layer of calcite, and a smooth inner layer composed mainly of calcium carbonate.
But how does a mollusk actually create a shell? An article from Earth & Sky explains:
The blood of a mollusk is rich in a liquid form of calcium. A soft, outer organ called the mantle concentrates the calcium in areas where it can separate out from the blood, forming calcium carbonate crystals. The mantle deposits sheets of the crystal in varying thicknesses. The individual crystals in each layer vary in shape and orientation
2006-10-29 02:56:03 · answer #2 · answered by richard_beckham2001 7 · 0⤊ 0⤋
Calcium Carbonate.
2006-10-29 03:00:04 · answer #3 · answered by mmd 5 · 0⤊ 0⤋
A shell is the hard, rigid outer covering, or integument, of certain animals. More specific scientific names include exoskeleton, carapace, and peltidium. A shell may be made of nacre (a combination of calcium and protein), chitin, bone and cartilage, or silica.While many sea animals produce exoskeletons, usually only those of mollusks (also spelled "mollusc") are normally considered to be "sea shells".
2006-10-29 02:54:26 · answer #4 · answered by Holly Holightly 2 · 0⤊ 0⤋
I believe it's Calcium Carbonate.
2006-10-29 02:55:14 · answer #5 · answered by Little One 4 · 0⤊ 0⤋
shell
2006-10-29 03:04:06 · answer #6 · answered by Anonymous · 0⤊ 0⤋