Identify and explain the characteristics of acoelomates and coelomates, including embryonic development, symmetry, and advantages of specific body plans.

here are the answers for Activity 3:

3.1

a) An acoelomate: A

b) A coelomate: B

3.2 Two phyla represented by body plan B (coelomate) are:

• Annelida
• Arthropoda

3.3 The tissue-filled layer (mesoderm) develops from the mesoderm embryonic layer.

3.4 The type of symmetry characteristic of organism B is bilateral symmetry.

3.5 Two advantages of an exoskeleton in arthropods:

• Protection: It provides a rigid outer covering that protects the soft internal tissues from physical injury and predators.
• Support and Muscle Attachment: It provides structural support for the body and a firm surface for muscles to attach, enabling movement.