Which is the simplest most primitive animal group?

Which is the simplest most primitive animal group?

Sponges are among the simplest forms of animal life.

Which are the simplest animals to have symmetry?

The simplest animals include the sponges (Porifera) and the Cnidaria. Sponges are unsymmetrical or radially symmetrical, with many cell types but no distinct tissues; their bodies contain numerous pores and sharp protective spicules.

Which group of animals includes the simplest animals with bilateral symmetry?

The simplest animals having bilateral symmetry (meaning that both the left and right sides of their bodies are mirror images of each other) include the invertebrate flatworms and roundworms. These animals live in water, on land, and as parasites in the body fluids of other organisms.

What are the simplest metazoans?

Sponges (porifera) are among the simplest of the metazoans (multicellular animals). Fossils of extinct sponges, such as the Archaeocyathids, have been found in Cambrian rock over 500 million years old.

What is a simple animal?

Simple animals are those without a fluid-filled body cavity between the outer body wall and the digestive tract. Examples of simple animals are sponges, corals, jellyfishes, sea stars, sea urchins, roundworms, and flatworms such as tapeworms.

What is the simplest animal with a brain?

Hydra
“Hydra have the simplest ‘brain’ in the history of the earth, so we might have a shot at understanding those first and then applying those lessons to more complicated brains,” he says.

Are cnidarians the simplest animals?

The cnidarians, or the jellyfish and their kin, are the simplest animal group that displays true tissues, although they possess only two tissue layers.

Which group of animals includes the simplest animals with bilateral symmetry quizlet?

Which group of animals includes the simplest animals with bilateral symmetry? (The name of this phylum is Platyhelminthes, which includes flatworms, the simplest animals to exhibit bilateral symmetry.)

What is a metazoan group?

Definition of metazoan : any of a group (Metazoa) that comprises all animals having the body composed of cells differentiated into tissues and organs and usually a digestive cavity lined with specialized cells. Other Words from metazoan Example Sentences Learn More About metazoan.

What are metazoans animals?

Animals (also called Metazoa) are multicellular, eukaryotic organisms in the biological kingdom Animalia. The scientific study of animals is known as zoology.

Which organisms are considered the simplest animals Why?

Sponges are considered to be one of the simplest animals, primarily because their bodies are not organized in organ systems or even tissues. Rather, sponges are made up of a grouping of cells that work together to contribute to meeting the daily needs of the sponge.

What are the different types of animal groups?

We’ll concentrate on the main animal groups, but will also take a look at a number of notable smaller animal types. There are two main types of animal: invertebrates and vertebrates. Invertebrates are animals that don’t have a backbone; vertebrates are animals that do.

What are the types of animals in biology?

Animals—complex, multicellular organisms equipped with nervous systems and the ability to pursue or capture their food—can be divided into six broad categories. In this article, you’ll discover the six main animal groups, ranging from the simplest (invertebrates) to the most complex (mammals). Invertebrates.

Do you know the collective names of some animals?

While some animals’ collective names have become quite well-known over the years, most are still fairly obscure, and some are just downright strange. English is a strange language, and nothing is stranger than the variety of collective nouns assigned to groups of particular animals.

What is your favorite group of invertebrate animals?

What is your favorite group of invertebrate animals? 1 Sponges 2 Cnidarians 3 Platyhelminthes 4 Echinoderms 5 Mollusks 6 Nematodes 7 Arthropods 8 Annelids 9 Chordates