metamere
An earthworm moves through the soil, its body made of many repeating metameres.
Noun: 1. A body segment in a segmented animal: In biology, a metamere is one of a linear series of similar, repeating body segments found in certain animals, such as earthworms, centipedes, and some marine worms. These segments are arranged along the longitudinal axis of the body.
The term "metamere" is a specialized biological term used to describe the segmented body plan of certain invertebrates. It is primarily used in scientific and academic contexts, such as zoology, anatomy, and evolutionary biology.
- The earthworm's body is composed of many metameres, each containing similar sets of muscles and nerves.
- In annelids, each metamere can function somewhat independently.
- The study focused on the developmental genetics that controls the formation of each metamere.
- Metameric segmentation: This phrase refers to the overall condition of having a body divided into metameres. It is a key characteristic of the phylum Annelida and other related groups.
- The principle of metameric segmentation is fundamental to understanding annelid anatomy.
- Metamerism (noun): The state or condition of being composed of metameres; serial segmentation.
- The evolutionary advantage of metamerism is a topic of ongoing research.
- Metameric (adjective): Of or relating to metameres; exhibiting segmentation.
- The metameric structure allows for greater flexibility and control of movement.
- Segment: A part into which something is divided. (Note: In a biological context, "segment" is a more general synonym for "metamere".)
- Somite: In embryology, a segment of the body of a vertebrate embryo. (This is a related but distinct concept, primarily used for vertebrates.)
The concept of a metamere is central to the biology of segmented animals. It is important to distinguish it from general body parts. A metamere specifically implies a repeating, homologous unit in a series that makes up the body's length. This segmentation can be visible externally (as in an earthworm's rings) and is often reflected in the internal organization of muscles, nerves, and circulatory structures.
An earthworm moves through the soil, its body made of many repeating metameres.
- one of a series of similar body segments into which some animals are divided longitudinally