Red algae

Definition

Red algae are a group of primarily multicellular, photosynthetic eukaryotes found mainly in marine environments. They belong to the phylum Rhodophyta and are characterized by their red pigmentation due to phycoerythrin.

5 Must Know Facts For Your Next Test

1. Red algae possess chlorophyll a and d, along with accessory pigments such as phycoerythrin and phycocyanin.
2. The cell walls of red algae contain agar and carrageenan, which are used commercially in food and industrial applications.
3. They reproduce both sexually and asexually; sexual reproduction often involves complex life cycles with alternation of generations.
4. Red algae can be found at greater depths in the ocean compared to other types of algae due to their ability to absorb blue light.
5. Some species of red algae contribute to the formation of coral reefs through the deposition of calcium carbonate.

Review Questions

Related terms

Chlorophyta:

A division of green algae characterized by their green color due to chlorophyll a and b.

Phycobiliproteins:

Accessory pigments found in cyanobacteria and certain algae like red algae, aiding in capturing light energy for photosynthesis.

Carrageenan: A substance extracted from red seaweeds used as a thickening or gelling agent in food products.