Pre AP Biology -EVO 1.1 Theory of Evolution- MCQ Exam Style Questions -New Syllabus
Pre AP Biology -EVO 1.1 Theory of Evolution- MCQ Exam Style Questions – New Syllabus 2025-2026
Pre AP Biology -EVO 1.1 Theory of Evolution- MCQ Exam Style Questions – Pre AP Biology – per latest Pre AP Biology Syllabus.
▶️ Answer/Explanation
The correct answer is b. slugs.
A radula is a specialized anatomical structure found in mollusks.
It functions as a chitinous, toothed ribbon used for scraping or cutting food.
Slugs and snails belong to the class Gastropoda, which characteristically possess this organ.
Lobsters (arthropods) use mandibles rather than a radula for feeding.
Worms (like annelids) and corals (cnidarians) lack this specific molluscan structure.
Therefore, among the choices provided, only the slug possesses a radula.
▶️ Answer/Explanation
The correct answer is d. Bivalvia.
Clams, scallops, and mussels all belong to the phylum Mollusca.
They are specifically categorized under the class Bivalvia because they possess two hinged shells (valves).
Cephalopoda includes organisms like octopuses and squids with prominent heads and tentacles.
Scaphopoda refers to “tusk shells,” which are elongated and tubular.
Gastropoda includes snails and slugs, which typically have a single spiral shell or no shell at all.
Therefore, a dish with clams, scallops, and mussels consists entirely of Bivalves.
▶️ Answer/Explanation
The phylum Chordata is defined by four primary diagnostic characteristics.
All chordates possess a notochord, which provides skeletal support.
They feature a dorsal hollow nerve cord that develops into the central nervous system.
Pharyngeal slits (or gill slits) are present at some stage of development.
A post-anal tail is a muscular extension extending past the anus.
These four traits must appear during the life cycle for an animal to be a chordate.
Therefore, the correct option is d.