Phylum Nematoda

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Phylum Nematoda

A few things we would want to know about these worms:

These species is very abundant. They can live everywhere and in huge numbers.

Their parasitic forms can infect virtually every type of animal and many plants

Some are extremely small and others can grow to the size of about 1 meter.

Approximately 25,000 named species.

Caenorhabditis elegans (C.Elegans) serve as an invaluable model system in Biology

It is a free-living, transparent nematode, about 1 mm in length, that lives in temperate soil environments.

They serve as a prominent model system because :

Space saving and inexpensive to care for.

Mutants are available.

Complete genome has been sequenced.

Short generation time for experiments.

Complete fate map is known. In other words, scientists know what each ell in the developing body will differentiate into.

All neural connections are known.

Transparent cuticle allows us to easily observe tagged cells without dissecting and processing the animal.

Possesses eutely which means that every individual within that species have the same number of cells

Possess unique muscles:

Only have longitudinal muscles which are arranged

in 4 bands.

Muscle Arm that extends to either the ventral or dorsal nerve. Although, not unique to nematodes, this arrangement is very unusual; in most animals the nerve processes extend to the muscle, rather than the other way around.