[Campbell Biology P.728] Which of the following statements correctly distinguishes between a... | Practice Question

Which of the following statements correctly distinguishes between animals with bilateral symmetry and animals with radial symmetry, according to the provided text?

  • A: Bilateral animals are typically sessile or planktonic, while radial animals tend to move actively from place to place.
  • B: Radial animals typically have sensory equipment concentrated at the head end, whereas bilateral animals can meet the environment equally well from all sides.
  • C: Bilateral animals generally possess a central nervous system ("brain") to coordinate complex movements, while radial animals are often found as jellies.
  • D: Both bilateral and radial symmetry types have existed for approximately 770 million years.

Explanation

According to the 'Symmetry' section, bilateral animals like arthropods and mammals typically move actively and have sensory equipment concentrated at the head, including a central nervous system 'brain' to coordinate complex movements. Radial animals, such as jellies, are often sessile or planktonic and meet the environment equally well from all sides.