Question

Select the phylum that has jointed appendages:

• A. Flatworm
• B. Roundworm
• C. Arthropod
• D. Cnidaria

Answer 1

The correct option is C

Arthropod

The correct option is option C.

Explanation for the correct option:

1. Arthropods are members of the Arthropoda phylum.
2. They are segmented invertebrates with a strong exoskeleton and paired jointed appendages.
3. Moving, chewing food, perceiving the environment, and flying are all done with the jointed appendages.

Explanation for the incorrect options:

Option A:

1. Flatworms are members of the Platyhelminthes phylum.
2. They are soft-bodied invertebrates with a flat, unsegmented body.
3. They are devoid of circulatory and respiratory systems.
4. A simple diffusion process allows them to take in oxygen and nutrients.
5. They are devoid of any joint attachments.

Option B:

1. The phylum Nematoda includes roundworms.
2. They can be found in a variety of settings.
3. They are quite little, measuring from$0.1$ to $2.5\mathrm{mm}$ in length.
4. The majority of roundworms are parasitic.
5. Their digestive system is tubular, with openings on both ends.
6. They don't have any appendages that can be joined together.

Option D:

1. Phylum Cnidaria is a phylum of aquatic organisms that includes over eleven thousand species that live in both freshwater and marine settings.
2. Cnidocytes, a type of cell utilized for capturing its prey, are a specific feature of Cnidaria.
3. They can be found in the form of swimming medusae or sessile polyps.
4. They don't have any appendages that can be joined together.

Final answer: The phylum that has jointed appendages is Arthropoda.