Parasitic worms have a highly developed __ system.
Multiple Choice
digestive
nervous
respiratory
muscular
reproductive
The correct answer and explanation is:
Correct Answer: Reproductive
Explanation:
Parasitic worms, also known as helminths, have a highly developed reproductive system. This adaptation is crucial to their survival strategy as parasites living in host organisms. Their environment inside the host is often hostile due to the immune system, and their chances of reaching new hosts are relatively low. Therefore, they compensate for this by producing a very large number of offspring, increasing the likelihood that at least some will reach new hosts and continue the life cycle.
There are three main groups of parasitic worms:
- Nematodes (roundworms)
- Cestodes (tapeworms)
- Trematodes (flukes)
In all three groups, the reproductive system is among the most prominent and complex organ systems. For example:
- Tapeworms can contain thousands of reproductive segments called proglottids, each with male and female reproductive organs.
- Flukes often exhibit hermaphroditism (having both male and female organs), allowing them to reproduce efficiently without needing a mate.
- Roundworms, though usually dioecious (having separate sexes), produce vast quantities of eggs or sperm.
On the other hand, their digestive, muscular, nervous, and respiratory systems are often simple or even reduced. Some parasitic worms, like tapeworms, lack a digestive system entirely, absorbing nutrients directly through their body surface from the host’s intestines.
Their nervous and muscular systems are sufficient for basic movement and environmental sensing but are not as developed as their reproductive organs. The respiratory system is typically absent, as many rely on anaerobic respiration (without oxygen) in the low-oxygen environments of the host body.
Summary:
Parasitic worms have a highly developed reproductive system, which allows them to produce large numbers of offspring to ensure the continuation of their species despite the challenges of their parasitic lifestyle.