Which of the following are characteristics of the class Adenophorea?
Class Adenophorea
- amphids always post-labial, variable shape, pore-like to elaborate.
- deirids not seen.
- phasmids generally absent.
- hypodermal glands present (excretory?)
- simple non-tubular excretory system when present.
- three caudal glands commonly opening through a spinneret at the tail tip.
What are the main characteristics of nematodes?
Characteristics of Nematoda
- Their body is bilaterally symmetrical and triploblastic.
- They are cylindrical in shape.
- They exhibit tissue level organization.
- Their body has a cavity or pseudocoelom.
- The alimentary canal is distinct, with the mouth and the anus.
- They are sexually dimorphic.
What are the general characteristics of Aphasmids?
Mainly, they are free-living in soil and water; however, there are a few parasitic forms of aphasmids. As the alternate name implies, they do not have phasmids, and the amphids are located posteriorly on the head region. In fact, they have no sensory bristles or papillae on the head and body.
What is the characteristics of roundworms?
Roundworms (nematodes) are bilaterally symmetrical, worm-like organisms that are surrounded by a strong, flexible noncellular layer called a cuticle. Their body plan is simple. The cuticle is secreted by and covers a layer of epidermal cells.
What is the difference between the class Adenophorea and Secernentea?
Most Adenophorea are non-parasitic. Free-living nematodes generally feed on bacteria, fungi, and protozoans. Secernentea are almost all parasitic and primarily terrestrial. Their hosts include plants, invertebrates, and vertebrates.
Which of the following are characteristics of the nematode class Secernentea?
Characteristics of Secernentea are:
- Amphid apertures are pore/slit-like.
- Derids are present in some; located near nerve ring.
- Phasmids are present; posterior.
- Excretory system is tubular.
- Cuticle is striated in two to four layers; lateral field is present.
- Three esophageal glands; esophageal structure varies.
What are 2 characteristics distinguish nematodes from other invertebrates?
Shape and Body Structure However, nematodes have thread-like, cylindrical bodies, and the name of the worm derives from the Greek word for thread. Their bodies are also non-segmented, unlike earthworms. Nematodes are bilaterally symmetrical, meaning both halves of their bodies are identical.
What characteristics set the Nematomorpha apart from the nematoda?
The main difference between Nematomorpha adults and Nematoda adults is the degenerate gut in the Nematomorpha. The role of the adults is not feeding, but reproduction and dispersal, and they have a featureless body, as the name, hair worm, suggests.
What are flatworms characteristics?
The main characteristics of flatworms (Figure below) include:
- Flatworms have no true body cavity, but they do have bilateral symmetry.
- Flatworms have an incomplete digestive system.
- Flatworms do not have a respiratory system.
- There are no blood vessels in the flatworms.
What are flatworms write any two characteristics of roundworms?
As the name implies, roundworms are cylindrical in shape. Like flatworms, roundworms have excretory, nervous, and reproductive systems….Anatomy of Roundworms.
| Flatworms (Platyhelminthes) | Roundworms (Nematoda) |
|---|---|
| Acoelomate (no body cavity) | Pseudocoelem (partial body cavity) |
What is the meaning of Adenophorea?
Adenophorea. A subclass of nematodes characterized by reduced or absent caudal papillae and an excretory system lacking lateral canals. Its organisms are usually infective to their final host.
What is the main difference between Adenophorea and Secernentea?
How big do adenophoreans get?
The majority of adenophoreans are free-living, microbotrophic, and aquatic nematodes. Only a few species are plant parasitic, invertebrate parasites, or vertebrate parasites. They range in size from microscopic to as long as 3.25 ft (1 m) in exceptional cases.
Why do adenophoreans have bursae?
Muscles move the stylet in and out, allowing the worms to puncture cells. Once opened, the worm will empty the contents of the cell. Male adenophoreans sometimes have thin cuticle extensions on both sides of the anus called bursae, which are fluid-filled body sacs. When present, bursae are used to hold females during copulation.
How do adenophorean worms puncture cells?
Adenophorean worms generally have some form of stylet, a hard, sharp spear, which is used for feeding. Muscles move the stylet in and out, allowing the worms to puncture cells. Once opened, the worm will empty the contents of the cell.
What is the habitat of a secernentean?
Secernenteans are distributed worldwide in terrestrial environments, and only rarely in regions containing water habitats. Secernenteans show considerable diversity in their habitats, including free-living microbotrophs, plant parasites, invertebrate parasites, and vertebrate parasites.
