bio s88 definitios - annelids

Trochozoa:

A clade of protostome animals that includes annelids and mollusks, characterized by the presence of a trochophore larval stage.

Echiura:

A group of unsegmented, burrowing marine worms, sometimes considered part of Annelida.

spoon worms

Pogonophora/Siboglinidae:

A family of deep-sea, tube-dwelling annelids that lack a digestive system and rely on symbiotic bacteria for nutrition.

beard worms

Sipuncula:

A group of unsegmented, marine worms known as peanut worms, characterized by an introvert that can retract into the trunk.

Sedentaria:

A subclass of annelids that includes sedentary, tube-dwelling worms such as earthworms and some polychaetes

Errantia:

A subclass of actively mobile polychaete worms that exhibit well-developed parapodia and sensory structures.

Clitellata:

A class of annelids, including earthworms and leeches, that possess a clitellum, which is involved in reproduction.

Hirudinidae:

A family of leeches within Clitellata, known for their blood-sucking habits and anticoagulant secretion.

Setae

: Bristle-like structures found on annelids, aiding in locomotion or anchoring.

Parapodia:

Paired, fleshy, lateral appendages found in polychaetes, used for locomotion and respiration.

Segmentation:

The division of an animal’s body into repeated sections, common in annelids.

Proboscis:

An extendable feeding structure used by some annelids and other invertebrates.

Forepart:

The anterior section of an animal's body, often including sensory and feeding structures.

Trunk:

The main body region, excluding the head and tail.

Opisthosoma:

The posterior body region in some annelids, such as Pogonophorans.

Introvert:

A retractable anterior structure found in some worm-like invertebrates, including Sipuncula.

Palps:

Sensory appendages located on the head, used for feeding and environmental perception.

Cirri:

Thin, filamentous appendages, often sensory or used for locomotion.

Prostomium:

The first anterior segment of an annelid’s body, located before the mouth.

Peristomium:

The segment surrounding the mouth, often bearing tentacles or sensory structures.

Pygidium:

The posterior-most segment of an annelid’s body, containing the anus.

Pharynx:

A muscular, sometimes eversible, feeding structure in many annelids.

Notopodium:

The dorsal lobe of a parapodium, often associated with respiration.

Neuropodium:

The ventral lobe of a parapodium, often used for locomotion.

Acicula:

Stiff, chitinous rods that provide structural support to parapodia.

Cuticle:

A protective, outer layer of an annelid's body, secreted by epidermal cells

Clitellum:

A glandular band on clitellate annelids that secretes a mucous cocoon for eggs

Crop:

A storage chamber in the digestive system, used to temporarily hold ingested food.

Gizzard:

A muscular organ that grinds food particles, aiding in digestion.

Nephridia:

Excretory organs that function in waste removal, similar to kidneys.

Nephrostome:

The ciliated, funnel-like opening of a nephridium, collecting waste.

Nephridiopore:

The external opening through which excretory waste is released.

Statocyst:

A sensory organ used to detect balance and orientation.

Nuchal organs:

Paired, chemosensory structures found in polychaetes, aiding in detecting environmental chemicals.

Atoke:

The non-reproductive, anterior portion of certain polychaetes.

Epitoke:

A sexually mature, reproductive individual or posterior region in some polychaetes, often adapted for swarming reproduction

Architomy:

A form of asexual reproduction where the body splits into fragments that regenerate

Paratomy:

A type of asexual reproduction where new individuals form before separating from the parent body

Deposit feeding:

A feeding mode where an animal ingests organic material from sediments

Mucous-net feeding:

A feeding strategy where an organism secretes mucus to trap food particles before ingestion.

Suspension feeding:

A strategy where an animal filters food particles from water

Blood meals:

A feeding habit in which an animal consumes blood, as seen in leeches.

Chemoautotrophy:

A nutritional strategy where organisms, such as Pogonophora, derive energy from chemical reactions (e.g., hydrogen sulfide oxidation) rather than consuming organic matter.