Planaria is diploblastic and Hydra is triploblastic.

Are Planaria triploblastic?

Characteristics. Flatworms are flattened and have bilateral symmetry. They are triploblastic (have 3 embryonic tissue layers: ectoderm, mesoderm, and endoderm) and therefore have organ-level of organization.

Are flatworms diploblastic?

Are flatworms diploblastic or triploblastic? Flatworms are triploblastic. This means they are derived from three germ layers: the endoderm, the ectoderm, and the mesoderm. ... Flatworms are acoelomates, meaning that their gastrovascular cavity is a gut, not a body cavity.

What is Planaria classified as?

planarian, (class Turbellaria), any of a group of widely distributed, mostly free-living flatworms of the class Turbellaria (phylum Platyhelminthes). Planaria is the name of one genus, but the name planarian is used to designate any member of the family Planariidae and related families.

Are Planaria Cephalized?

The planarian is the simplest living animal having a body plan of bilateral symmetry and cephalization. The brain of these free-living flatworms is a bilobed structure with a cortex of nerve cells and a core of nerve fibres including some that decussate to form commissures.

13.2.6 Body Cavities - Acoelomates, Pseudocoelomates, and---

28 related questions found

Are Planaria segmented?

Planarians are flat, soft-bodied worms with a triploblastic body plan and lacking visible segmentation. Many hundred species are known, including fresh- and seawater dwellers and even terrestrial forms.

Are Planaria unicellular or multicellular?

Planarians are simple multicellular animals known as flatworms. They can regenerate parts of their bodies using adult stem cells called neoblasts.

Is Planaria a cnidarian?

Like the Hydra and other members of the Phylum Cnidaria, the planarian has a cul-de-sac gut, one with only one opening, the mouth. 6. To capture prey animals, the planarian moves from place to place.

How do planaria reproduce?

Asexual freshwater planarians reproduce by tearing themselves into two pieces by a process called binary fission. The resulting head and tail pieces regenerate within about a week, forming two new worms.

Are Flatworms segmented?

Three types of worms with different body types will be explored in this lesson: Flatworms, which have ribbon-like bodies with no body cavity. Roundworms, which have a body cavity but no segments. Segmented worms, which have both a body cavity and segmented bodies.

Why are Flatworms considered triploblastic?

Flatworms are considered triploblastic, meaning there are three germ layers in the embryo (ectoderm,endoderm and mesoderm) and so a layer that gives rise to connective tissue and muscle in the adult. They then use muscle as well as ventral cilia to move.

Are nematodes diploblastic?

Are nematodes diploblastic or triploblastic animals? Just like platyhelminthes, nematodes are triploblastic organisms, meaning that they have three germ layers (the ectoderm, mesoderm and endoderm).

Are roundworms triploblastic?

The Nematoda, like most other animal phyla, are triploblastic and possess an embryonic mesoderm that is sandwiched between the ectoderm and endoderm. ... Furthermore, the nematodes, or roundworms, possess a pseudocoelom and consist of both free-living and parasitic forms.

What are the structures of a planarian?

Planaria have three germ layers (ectoderm, mesoderm, and endoderm), and are acoelomate (they have a very solid body with no body cavity). They have a single-opening digestive tract; in Tricladida planarians this consists of one anterior branch and two posterior branches.

Are Planaria male or female?

All planarians are hermaphrodites, so their reproductive system has a male and a female part. Both parts communicate with the surface of the body via a single opening called gonopore, which is located on the ventral side of the posterior half of the body.

What type of symmetry does a planarian have?

First, planarians have bilateral symmetry with two nerves extending the length of the body, an enlarged "brain" (ganglion cell), and two eye spots. The eye spots are sensitive to light.

Do flatworms have an exoskeleton?

Explanation: Exoskeleton and endoskeleton are absent in members of phylum Platyhelminthes. These are the first group of animals where three primary germ layers develop, i.e. ectoderm, mesoderm and endoderm.

Do flatworms have a circulatory system?

Flatworms have no circulatory system. Animals without a circulatory system have limited abilities to deliver oxygen and nutrients to their body cells because of the way that molecules behave. As molecules spread through water, they become less concentrated as they move away from their source.

How do Planaria regenerate?

Regeneration in planarians depends on the presence of stem cells called neoblasts. These cells are distributed throughout the body and, when part of the worm has been amputated, they are activated to reform the tissues that have been removed (Wagner et al., 2011).

Is Planaria a unicellular?

Planaria:It is a multicellular organism which possesses a high regenerative capacity. To our surprise, these organisms can reproduce sexually as well as asexually.

Is fungi is unicellular or multicellular?

Fungi can be single celled or very complex multicellular organisms. They are found in just about any habitat but most live on the land, mainly in soil or on plant material rather than in sea or fresh water.

Is a worm unicellular or multicellular?

Earthworms belong to the Animalia kingdom. They are multicellular organisms that are also eukaryotic; this means that their cells have nuclei.