Arthropoda Merostomata Flashcards

Questions and Answers

What is the definition of Cephalothorax?

The body region of some arthropods that consists of a head fused with a thorax (correct)

A pincerlike claw

Eyes made of many individual light detectors

The part of the body that contains the digestive organs

What is the part of the body that contains the digestive organs?

abdomen

What characterizes a compound eye?

Basic photoreception units

Made of many individual light detectors (correct)

Single lens imaging

Eyes that consist of a lens

What is a carapace?

shield-like plate covering the cephalothorax Signup and view all the answers

What is the function of the telson in crustaceans?

used for propulsion Signup and view all the answers

What are chelicerae?

Appendages in arachnids modified for grasping Signup and view all the answers

What are pedipalps?

pair of mouthparts in chelicerates modified to grab prey Signup and view all the answers

What is the definition of chelae?

pincerlike claw Signup and view all the answers

What are gnathobases?

median basic process on certain appendages for biting or crushing food Signup and view all the answers

What are chilaria?

pair of degenerated legs posterior to the walking legs Signup and view all the answers

What are walking legs?

five pairs of long, jointed legs used for walking Signup and view all the answers

What are gill opercula?

first pair of book gills protecting other gills Signup and view all the answers

What are book gills?

respiratory structure of aquatic chelicerates Signup and view all the answers

Study Notes

Body Regions and Structures

Cephalothorax: Fused head and thorax region present in various arthropods, specifically arachnids and higher crustaceans.
Abdomen: Body section that houses the digestive organs of the organism.
Carapace: Shield-like structure that covers the cephalothorax, primarily in certain crustaceans.
Telson: Central part of the abdominal region in crustaceans, facilitating propulsion and is the posterior projection of the last body segment.

Visual and Appendage Features

Compound Eye (Lateral Eye): Composed of numerous ommatidia, this visual organ has multiple individual light detectors, allowing differentiation of brightness and color.
Chelicerae: A pair of modified appendages in arachnids, functioning as pincer-like claws for capturing prey, located in front of the mouth.
Pedipalps: Second set of appendages in arachnids, typically modified for grasping food, serving as mouthparts.
Chelae: Refers to the pincer-like claws used for defense and catching prey.

Feeding Structures

Gnathobases: Specialized processes found on certain arthropod appendages, designed for biting or crushing food.
Chilaria: Reduced leg pairs located behind the walking legs, serving a diminished function.

Locomotion and Breathing

Walking Legs: Five pairs of elongated, jointed legs that facilitate movement and are equipped with gills on their tops for respiration.
Gill Opercula: The operculum is the first pair of book gills that protect other gills and cover the exit for reproductive cells.
Book Gills: Respiratory structures in aquatic chelicerates, resembling layered pages, that enable gas exchange when seawater flows between the gills.

Description

Test your knowledge on the phylum Arthropoda and class Merostomata with these flashcards focused on horseshoe crabs. Each card highlights critical terms including cephalothorax, abdomen, and compound eyes, essential for understanding this unique species.