Ascaris is an animal genus comprised of intestinal roundworms. Ascaris lumbricoides lives in humans, and ascaris suum in pigs. Although the male and female worms look similar, there are several characteristics that distinguish the two sexes, both externally and internally. Externally, the sexes can be identified by size and the presence or absence of bodily structures. Internally, they can be distinguished by their reproductive organs.
Examine the size of the ascaris. Females are usually wider around and grow to be 20-40 cm long, while males are usually thinner and grow to be 15-30 cm long.
Examine the posterior end of the worm. Female worms are straight while males are hooked.
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Examine the posterior opening. A male worm has pineal spicules, or spine-like extensions, near its opening. It will also have papillae, or bump-like protrusions, in front and behind this opening. Females lack these structures.
Examine its body. Females will have a reproductive opening on the posterior third of its body. Males will lack any such opening.
Examine the posterior region of the body cavity.
Find the tube-shaped reproductive organs.
Identify the shape of the organ. A female will have two tubes that join together to form a "Y," while males have one straight tube.