Question

В чем состоит отличие Круглых червей от Плоских червей?   1.Имеют кожно-мускульный мешок 2.Используют для дыхания кислород 3.Являются гермафродитами 4.Питаются готовыми органическими веществами 5.Рот расположен на брюшной стороне тела 6.Промежутки между органами заняты клетками паренхимы

Answer 1

1.Имеют кожно-мускульный мешок

 

Answer 2

#### Difference between Roundworms and Flatworms Roundworms and flatworms are two different types of worms that belong to the phylum Nematoda and Platyhelminthes, respectively. While they share some similarities, there are several key differences between them. Let's explore these differences in more detail: **1. Body Structure:** - Roundworms, also known as nematodes, have a cylindrical body shape with a distinct outer covering called a cuticle. This cuticle provides support and protection to the worm's body. - Flatworms, on the other hand, have a flattened body shape, hence the name "flatworms." They lack a rigid body cavity and have a soft, flexible body. **2. Respiratory System:** - Roundworms do not have specialized respiratory organs. They obtain oxygen through their body surface by simple diffusion. - Flatworms also lack specialized respiratory organs. They rely on their thin body structure and the process of diffusion to exchange gases with their environment. **3. Reproductive System:** - Roundworms are dioecious, meaning they have separate male and female individuals. They reproduce sexually, with the male worm transferring sperm to the female worm during copulation. - Flatworms, on the other hand, can be hermaphroditic, meaning they have both male and female reproductive organs in the same individual. They can reproduce both sexually and asexually. **4. Feeding Habits:** - Roundworms are heterotrophic organisms that feed on a variety of organic matter, including decaying plant material, bacteria, fungi, and other small organisms. - Flatworms also exhibit heterotrophic feeding habits. Some flatworms are free-living and feed on small organisms, while others are parasitic and obtain nutrients from their hosts. **5. Body Symmetry:** - Roundworms exhibit bilateral symmetry, meaning their body can be divided into two equal halves along a single plane. - Flatworms also exhibit bilateral symmetry, with a distinct head region and a flattened body shape. **6. Body Organization:** - Roundworms have a well-developed body cavity called a pseudocoelom, which separates the internal organs from the body wall. The space between the organs is filled with fluid. - Flatworms lack a body cavity and have a solid body structure. The space between the organs is occupied by parenchyma cells, which provide support and perform various functions. These are some of the key differences between roundworms and flatworms. It's important to note that both groups encompass a wide range of species with diverse characteristics and adaptations.