It is a very common mistake to look at a spider crawling on the wall and call it an 'insect' or a 'bug'. In biology, spiders belong to an entirely different class of animals, and their leg count proves it.
Spider Legs: Exactly 8 legs.
Insect Legs: Exactly 6 legs.
Biological Class: Spiders belong to the class 'Arachnida', not 'Insecta'.
Every spider in the world has exactly 8 legs (four pairs).
If you see a tiny creature crawling in your house and you want to know what it is, just count the legs. If it has 8 legs, it is definitely a spider.
This is a basic classification rule in Biology:
Therefore, because a spider has 8 legs, it cannot be classified as an insect.
A spider has exactly 8 legs (four pairs). Because of this, spiders are classified as Arachnids and not as Insects (which only have 6 legs).
Why Is Cell Called the Structural and Functional Unit of Life?
Cell is the structural unit because all organisms are made of cells. It is the functional unit because all life processes occur at cellular level. Cell theory, Hooke, Schleiden, Schwann explained.
Why is the Plasma Membrane Called a Selectively Permeable Membrane?
Learn why the plasma membrane is called a selectively permeable membrane. Understand the lipid bilayer and how it controls the entry and exit of molecules.
Why Is Respiration Considered to Be an Exothermic Reaction?
Respiration is exothermic because it releases energy in the form of heat and ATP. Glucose + O₂ → CO₂ + H₂O + energy. Learn the full explanation with FAQs.
Why is Respiration Considered an Exothermic Reaction?
Learn why respiration is classified as an exothermic reaction. Understand how glucose oxidation releases energy as heat and ATP.
What are Xerophytic Plants?
Learn about xerophytic plants (xerophytes), their special adaptations to survive in desert environments, and examples like Cactus and Aloe Vera.
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