Parasitic adaptations in Taenia and Wuchereria

Adaptation may be defined as the fitness of an organism to live in its specific habitat or environment. Taenia and Wuchereria are modified morphologically as well as physiologically to live in their particular environment.

Morphological Adaptation:

These are adapted to parasitic mode of life having some:

Degeneration or loss of organs or systems.

Attainment of new organs.

Degeneration:

Locomotory Organs:

As these parasites live for their entire life in the body of a host, the locomotory organs are reduced.

Alimentation:

As the parasites live on digested or semi-digested food of the host, there is reduction in their alimentation and digestive glands. Food is absorbed directly through the general body surface.

Sensory Organs:

Sensory organs are also simple. Complicated sensory structures can also be correlated to sedentary life.

New attainment:

For food absorption, protection and attachment, attainment of new structures happen.

Cuticle:

The outer cuticle become highly modified and is so adapted as to resist against the digestive juice, passage of food. The cuticles become thin for food absorption.

Musculature:

The well developed musculature in tape worm enables them to distribute their elongated snake-like bodies throughout the length of the intestine of their host.

Organs for attachment:

All parasites develop suitable mechanisms for attachment with their hosts to be exterior or interior cavities. Tape worm scolex bears either four sucking cups for attachment. T.Solium also bear, the rostellum the contains a basal circlet of hooks.

Vast reproduction: Reproductive organs show significant development and adaptation to parasitism. There is a vast increase in the reproductive capabilities through greater egg production. In both tape worm and wuchereria, the interior of the body is mostly occupied by the genital organs. Tape worm is hermaphrodite, while Wuchereria is discussed.

In tape worms, body consist of a large number of segments or proglottids, each containing a single or double set of reproductive organs. Wuchereria has not sexual stage outside the host. Life history usually includes several larval forms for multiplication and for easy and sure transfer from one host to other.

Physiological Adaptations:

Osmo-regulation:

The osmotic pressure of the interior of the parasitic worms remains less than or same as that of their host, so that there is no difficulty in exchange of water.

Anaerobic Respiration:

Since Tania never set free oxygen, its evolutionary adaptation has resulted in a very low metabolic rate which requires a minimum amount of oxygen. So respiration is anaerobic type and energy is obtained by the fermentation of glycogen.

Anti-enzymes:

Tape worm and Wuchereria secrete anti-enzymes in order to protect them-selves from gastric juice and digestive enzymes.