Which of the following structures is present in gymnosperms but absent in pterophytes?

• A. Sporangia
• B. Vascular tissue
• C. Flagellated sperm
• D. Seeds

Answer: (D)

Verified step by step guidance

1. Understand the key difference between gymnosperms and pterophytes: Gymnosperms are seed-producing plants, while pterophytes (ferns) reproduce via spores and do not produce seeds.
2. Review the structures listed in the problem: Sporangia, vascular tissue, flagellated sperm, and seeds. Determine which of these is unique to gymnosperms.
3. Recognize that sporangia are present in both gymnosperms and pterophytes as they are involved in spore production. This structure is not unique to gymnosperms.
4. Identify that vascular tissue is also present in both gymnosperms and pterophytes, as both groups are vascular plants. This structure is not unique to gymnosperms.
5. Note that seeds are a defining characteristic of gymnosperms and are absent in pterophytes, which reproduce via spores. Therefore, seeds are the correct answer as the structure present in gymnosperms but absent in pterophytes.