In this lesson, we’ll learn about the external and internal biological differences between male and female Ascaris worms. This information will help us determine the sex of an Ascaris worm when asked to dissect one in a zoology, biology, or general science course.
What is an Ascaris Worm?
In this lesson, we’ll learn about the differences between male and female Ascaris worms; but first, let’s learn a little bit about these worms in general. Ascaris is a genus of roundworms that can be found in almost any type of habitat, including saltwater, freshwater, or on land. Ascaris worms can also cause disease when ingested by humans, horses, and pigs. Additionally, Ascaris are dioecious , meaning that there is a separate male and female worm.
Since there’s a separate male and female worm, there are some key differences between then, both externally and internally.
Ascaris worms are sexually dimorphic, which means that there are differences in body size, shape, color, and so forth between males and females. For example, the males are shorter in length than the females. Male Ascaris worms range from 15-31 cm in length, with the length of female Ascaris worms ranging from 20-49 cm, with an average length of 30 cm. Also, the males have a smaller diameter than females. Males’ diameter is usually 2-4 mm and the females’ diameter is 3-6 mm.
Besides size, one of the simplest ways to determine if an Ascaris worm is male or female is the presence or absence of a spicule. _A spicule is a hook-shaped organ located at the end of the male body used during reproduction to hold open the vulva of the female. Let’s now discuss the internal sexual organs present in males and females that differentiate them.
Like female humans, female Ascaris worms have ovaries that produce eggs. The oviduct then stores the eggs until fertilization begins. The genital pore is where sperm enters the body, and it also releases fertilized eggs. The uterus holds the fertilized eggs until the female is prepared to release them into the environment.
The male Ascaris worm has testes that produce the sperm, as well as a seminal vesicle, which is responsible for moving the sperm from the male to the female. The male’s vas deferens helps move the sperm from the testes to the seminal vesicle for storage.
Ascaris is a genus of roundworms. Ascaris worms are dioecious and sexually dimorphic, and can be found in almost any type of habitat.
External differences in males and females include length, with males being shorter than females; diameter, with males having a smaller diameter than females; and the presence of a spicule in males.Internal differences are apparent in the sexual organs in each sex. Females have ovaries that produce eggs, an oviduct that stores the unfertilized eggs, a genital pore that releases fertilized eggs, and a uterus that holds the fertilized eggs until they’re released into the environment. The male has testes that produce the sperm, a seminal vesicle ‘responsible for moving the sperm from the male to the female, and a vas deferens that helps move the sperm from the testes to the seminal vesicle for storage.