Which one of the following organisms has vascular tissues?
- A.Cladophora
- B.Penicillium
- C.Marsilea
- D.Anabaena
Correct answer
Explanation
The correct answer is C, Marsilea. Marsilea is a water fern, a pteridophyte, and pteridophytes are the first land plants with true vascular tissues, xylem and phloem.
Pteridophytes, such as ferns, horsetails (Equisetum), Selaginella and Marsilea, have a plant body divided into true roots, stem and leaves, with xylem and phloem to carry water and food. They reproduce by spores and lack seeds. Marsilea is a small aquatic fern often called the water clover because its leaves look like a four-leaf clover. Algae, fungi and bacteria have no such conducting tissue at all.
A is wrong: Cladophora is a green alga with a simple, branched, thread-like body and no vascular tissue.
B is wrong: Penicillium is a fungus, the source of the antibiotic penicillin, made of hyphae without any xylem or phloem.
D is wrong: Anabaena is a cyanobacterium (blue-green alga) that fixes nitrogen; it is a simple prokaryote.
Exam tip: pteridophytes are the first vascular plants, gymnosperms the first seed plants, angiosperms the flowering plants.
Practice Questions
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Show answer
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