What characteristic is commonly shared by organisms with deuterostome development?

• A. They develop the mouth before the anus during embryonic development.
• B. They develop the anus before the mouth during embryonic development.
• C. They have radial symmetry as adults.
• D. They exhibit a segmented body plan.

Answer: (B)

Verified step by step guidance

1. Understand the concept of deuterostome development: In deuterostomes, the first opening that forms during embryonic development becomes the anus, and the mouth forms later. This is a key characteristic that distinguishes them from protostomes, where the first opening becomes the mouth.
2. Identify the organisms that exhibit deuterostome development: Deuterostomes include groups such as echinoderms (like starfish and sea urchins) and chordates (which include vertebrates).
3. Recognize the significance of embryonic development patterns: The sequence of mouth and anus formation is crucial in classifying organisms into deuterostomes or protostomes, which are two major divisions of the animal kingdom.
4. Consider other characteristics of deuterostomes: While the development of the anus before the mouth is a defining feature, deuterostomes may also exhibit other traits such as bilateral symmetry during the larval stage and radial symmetry in some adult forms, like echinoderms.
5. Review the options given in the problem: The correct characteristic of deuterostome development is the formation of the anus before the mouth. Other options, such as radial symmetry or segmented body plans, may not universally apply to all deuterostomes.