parazoa

Thân thiện

A marine biologist carefully observes a parazoa specimen in a water tank.

Definition

Noun: 1. A taxonomic subkingdom of simple, multicellular animals: Parazoa refers to a group of organisms characterized by having a loose aggregation of cells without true tissues or organs. This subkingdom consists solely of the phylum Porifera (sponges).

Usage

The term is used primarily in formal biological and zoological classification to distinguish these simple animals from the more complex Metazoa (all other animals). - The subkingdom Parazoa includes only sponges, which lack the organized tissues found in other animals. - Biologists study Parazoa to understand the early evolution of multicellularity.

Advanced Usage

• In evolutionary biology: The term is used to discuss the branching point between simple colonial organisms and more complex, tissue-forming animals.
  • The transition from Parazoa to Eumetazoa marks a major step in animal evolution.

Variants and Related Words

• Parazoan (noun/adjective): An individual organism belonging to the Parazoa; relating to the Parazoa.
  • The parazoan body plan is fundamentally different from that of a jellyfish.

Synonyms

• Sponges (common name for the phylum Porifera, which constitutes the Parazoa).
• Porifera (the phylum name, often used interchangeably with Parazoa in a taxonomic context).

Antonyms

• Eumetazoa: The subkingdom comprising all animals with true tissues (all animals except sponges).
• Metazoa: Sometimes used broadly to mean all multicellular animals, but technically includes both Parazoa and Eumetazoa.

Học thuật

Noun

1. multicellular organisms having less-specialized cells than in the Metazoa; comprises the single phylum Porifera

Từ đồng nghĩa

• Parazoa
• subkingdom Parazoa