Ascaris (Male and Female)- Diagram

Ascaris is a well-known genus of the Phylum Nematoda. One of the renowned species of this genus is Ascaris lumbricoides, which is known for its parasitic properties and resides inside the small intestine. Ascaris are unisexual (Both male and female exist separately), having an unsegmented bilaterally symmetrical body possessing a pseudocoelom.

Classification of Ascaris

The table of biological classification of Ascaris is given below:

Common Name of Ascaris

Ascaris lumbricoides is also known as the Human Roundworm.

General Characteristics of Ascaris

Some general characteristic of Ascaris are:

Habitat And Distribution

• Ascaris lumbricoides, being the largest known endoparasite and cosmopolitan in nature, is predominately found inside the lumen (small intestine) of human beings. Another variant of Ascaris is also found in pig, called Ascaris suum. This variant is incapable of infecting humans.
• According to a study, there are 145 million people are affected with Ascaris lumbricoides infection.
• According to a study, 145 million people are affected with Ascaris lumbricoides infection.
• No intermediate host is involved. Infection is caused by consuming contaminated water or uncooked food.

Structure of Body

• It is pale yellowish or pinkish in colour, with the external layer of the cuticle being transparent, and thick. Cuticle provides protection from the external environment and helps in movement by making contact with body muscles.
• Body is unsegmented and cylindrical in shape, and bilaterally symmetrical.
• It has pseudocoelom. Furthermore, in both sexes, the pseudocoelom is not lined by the epidermis.
• A small triradiate mouth is present at the anterior side that is guarded by 3 broad lips, also called labia.
• Respiration occurs through simple diffusion.
• The organism has a straight complete digestive system with a mouth, muscular pharynx and an anus at the posterior side.
• Nervous system is of primary level of organisation with a nerve ring with multiple longitudinal nerve cords.
• Four longitudinal lines are present in both males and females – two lateral, one ventral and one dorsal line.

Reproduction in Ascaris

• Reproduction occurs through sexual reproduction.
• Sexes are separate .
• Male achieves a length of 15-30 cm and is thinner than a female with a diameter of 2-4 mm
• Females are longer than males and achieve a length of 20-35 cm and are thicker than males, around 4-5 mm in diameter.
• Male Reproductive Organ: At the posterior end of males, a vertically curved structure is present called a cloacal aperture through which two iso spicules arise called Penial Setae. The Penial Setae serve to open the female genital pore during copulation and help in the transference of sperm.
• Female Reproductive Organ: Females have a separate opening as a genital opening at the posterior half of their body. The posterior end is connected to the ovary through a "Y-shaped" structure i.e., the two straight tubes join together at the posterior end extending from the ovary.

Diagram of Ascaris

Given below is a diagram showing the male and female structure of Ascaris.

Difference between Male and Female Ascaris

The following table lists the salient differences between a male and female Ascaris:

Diseases Caused by Ascaris lumbricoides

Ascariasis, is the main disease caused by Ascaris lumbricoides. This disease results as a result of infestation of the worms in the small intestine.Multiple symptoms are displayed which include diarrhoea, vomiting, weight loss, etc. If the number of worms becomes extremely large, it leads to intestinal blockage. Sometimes, the Ascaris larvae migrate to the lungs resulting in pneumonia like symptoms.

If children get infested with Ascaris lumbricoides, they show stunted growth and are poorly malnutritioned.