Volvox Structure and Function (With Diagram)

This article will go over the volvox structure and function. This will also help you draw the structure and diagram of volvox.

Volvox structure and function

Volvox thallus is a mobile colony with a distinct shape and cell count. This thallus habit is known as coenobium.

The colony is about the size of a pin head and is hollow, spherical, or oval in shape. There are a fixed number of cells in a colony. The cells of a Volvox can range in size from 500 to 60,000. The cells are arranged in a single layer on the colony’s periphery and the colony’s centre is mucilaginous (Fig. 1A).

volvox structure and function

Volvox structure and function

Compared to cells at the posterior end, those at the anterior end have larger eye spots. When mature, the cells on the posterior side start to reproduce. As a result, the Volvox colony is spherical or circular and clearly polar. Volvox colony cells are of the Chlamydomonas type. Each individual cell has a mucilage sheath (Fig. 1 B).

The compression between cells gives the colony’s mucilage envelope an angular appearance. The cytoplasmic strands that connect the cells together. The cytoplasmic connections or strands are absent in some Volvox species.

Colony cells are typically pyriform, with a narrow anterior end and a broad posterior end. The cells are biflagellate, with two equal whiplash flagella that project outwards (Fig. 1 C). The plasma membrane encloses the cell’s protoplasm.

Each cell has a nucleus, a cup-shaped chloroplast containing one or more pyrenoids, an eye spot, and 2-6 contractile vacuoles. The cells of some Volvox species, such as V. globator and V. rousseletii, are of the Sphaerella type.

Photosynthesis, respiration, and excretion are all performed independently by colony cells. Colony movement is accomplished through coordinated flagellar movement. The coenobium reproduces in the same way.