Discuss the features that differentiate myriapods from roundworms.

Myriapods and roundworms are two distinct groups of animals belonging to the phylum Arthropoda and Nematoda respectively. The differences between these two groups of animals can be observed in various aspects such as body structure, habitat, feeding habits, reproduction, and other unique features. In the following steps, we will explore these differences in detail.

Myriapods are arthropods, which means they have a segmented body, jointed appendages, and an exoskeleton made of chitin. They include animals like centipedes and millipedes. Myriapods have multiple body segments, each with one or two pairs of legs. On the other hand, roundworms (also known as nematodes) have a simple, elongated, and cylindrical body shape without segments. Their body is covered by a tough cuticle, which serves as an exoskeleton.

Myriapods can be found in a wide range of terrestrial habitats like forests, grasslands, and under rocks or leaf litter. They are mainly land-dwelling animals. Roundworms, on the contrary, can be found in diverse environments, including soil, freshwater, and saltwater. Some roundworms can also be parasites of plants, animals, and humans.

Myriapods are primarily detritivores or carnivores. Millipedes feed mainly on decaying plant matter, while centipedes are predators that eat insects and other small animals. Roundworms have diverse feeding habits, which include feeding on bacteria, fungi, plant material, and even other nematodes. Some roundworm species, like the parasitic ones, can absorb nutrients directly from their host's body fluids or tissues.

Myriapods are mostly gonochoristic, meaning that they have separate male and female individuals. They reproduce sexually through the transfer of sperm from males to females, either indirectly or through copulation. Roundworms exhibit both sexual and asexual reproduction. Many species are dioecious (separate sexes), and fertilization occurs internally in the female. Other species can reproduce through a process called parthenogenesis, in which unfertilized eggs develop into new individuals.

One unique feature of myriapods is their numerous legs, which vary in number depending on the species. Centipedes have one pair of legs per body segment, while millipedes have two pairs of legs per segment. In contrast, roundworms do not have any legs or appendages, but they possess a simple nervous system and longitudinal muscles that enable them to move in a characteristic undulating motion. In summary, the main differences between myriapods and roundworms lie in their body structure, habitat, feeding habits, reproduction, and unique features. Myriapods are arthropods with segmented bodies and multiple pairs of legs, while roundworms have a simple, elongated, and unsegmented body shape. Myriapods are primarily terrestrial, whereas roundworms can be found in various environments, including soil, water, and as parasites.