Which species of green algae, commonly known as stonewort, is often mistaken for a plant?

The correct answer is Chara.

Key Points

• Chara is a genus of green algae belonging to the Charophyta division and is commonly referred to as stonewort.
• It is often mistaken for a plant due to its complex morphology, including stem-like structures and whorls of branchlets.
• Chara is found predominantly in freshwater environments like ponds and lakes, where it grows submerged.
• Unlike vascular plants, Chara lacks true roots, stems, and leaves but has rhizoids for anchoring and nutrient absorption.
• Its body structure and reproductive mechanisms make it one of the closest relatives to land plants within the algal group.

Additional Information

• Charophytes: A group of green algae that are the closest relatives to land plants, sharing similar cellular and reproductive structures.
• Rhizoids: Thread-like structures found in Chara that function similarly to roots, aiding in anchoring and nutrient absorption.
• Stonewort: The nickname "stonewort" comes from its calcified appearance due to the deposition of calcium carbonate on its surface.
• Reproductive Structures: Chara reproduces sexually using oogonia (female structures) and antheridia (male structures), which resemble plant reproductive organs.
• Ecological Role: Chara plays a vital role in aquatic ecosystems by oxygenating water, providing habitat for aquatic organisms, and stabilizing sediments.