Question 74
AOptions
BSolution
To determine which organism does not belong to the class of the other three, we need to classify them:
- Crab: Crabs belong to the class Malacostraca, which is part of the subphylum Crustacea, within the phylum Arthropoda. Crustaceans are primarily aquatic arthropods and typically have ten legs (including claws).
- Mite: Mites belong to the class Arachnida, within the phylum Arthropoda. Arachnids are characterized by eight legs (four pairs) and a body divided into two main segments (cephalothorax and abdomen).
- Scorpion: Scorpions also belong to the class Arachnida, within the phylum Arthropoda. Like mites, they have eight legs.
- Spider: Spiders are also members of the class Arachnida, within the phylum Arthropoda, and are known for their eight legs.
Therefore, mites, scorpions, and spiders all belong to the class Arachnida, while a crab belongs to the class Malacostraca (Crustacea). Hence, the crab does not belong to the same class as the other three.
CStrategy
For biology questions on classification, review the major phyla, classes, and orders within the animal kingdom. Focus on understanding the distinguishing characteristics (e.g., number of legs, body segments, habitat) that define these taxonomic groups.
DSyllabus Analysis
This question falls under General Science, specifically Biology (Animal Kingdom classification and basic taxonomy).
EQuestion Analysis
Medium. This question requires specific knowledge of animal classification, particularly distinguishing between crustaceans and arachnids based on their defining characteristics.