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Date of Award

5-2-1996

Document Type

Restricted Thesis: Campus only access

Degree Name

Bachelor of Science

Department

Biology

First Advisor

Dr. Roni Kingsley

Abstract

The gorgonian Leptogorgia virgulata is a member of the phylum Cnidaria. Animals of this very successful phylum are found mainly in marine environments although some species can live in fresh water. The gorgonian has an octomerous symmetry and is colonial (Hickman, Roberts, and Hickman, 1990). Like many invertebrates, the gorgonian produces calcified structures in the form of spicules from calcium and bicarbonate ions. These calcified spicules provide protection against predators, support for anchoring and locomotion, sensory functions, and possibly a means for regulating potentially toxic levels of intracellular calcium (Kingsley, 1990).

Kingsley (1990) summarizes gorgonian spicule formation as follows. The calcification process begins intracellularly within vacuoles of scleroblasts, the spicule forming cells. The organic matrix, which is synthesized by rough endoplasmic reticula and golgi bodies, is transported. Calcium ions are transported by electron-dense bodies to the spicule forming vacuoles. The organic matrix apparently regulates the crystal formation. The vacuoles, and eventually the scleroblasts, increase in size from the continued growth of the calcium carbonate spicules. The spicules ultimately become extracellular when the vacuole and plasma membranes fuse, exposing the spicule. The spicule can continue to grow extracellularly with the aid of secondary sclerocytes (Kingsley, 1990).

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