Describe Rhodophyta phylum Charophyta. Including diagrams. 4pages and 4references.
Rhodophyta, also known as red algae, is a phylum of marine algae that are found in both tropical and temperate waters worldwide. They are known for their red pigmentation, which is a result of the presence of the pigment phycoerythrin in their cells. Rhodophyta can range in size from tiny, single-celled organisms to large, multicellular seaweeds.
One of the key characteristics of Rhodophyta is their cell wall composition. Unlike most other algae, red algae have cell walls made of cellulose and a unique polysaccharide called agar. Agar is a gelatinous substance that is used in a variety of applications, including as a culture medium in microbiology and as a thickening agent in food products. The presence of agar in the cell walls of red algae gives them a distinct texture and consistency compared to other algae.
Rhodophyta are capable of both sexual and asexual reproduction. In sexual reproduction, male and female gametes are released into the water, where they fuse to form a zygote. This zygote then develops into a new organism. In asexual reproduction, red algae can reproduce through fragmentation, where a piece of the algae breaks off and grows into a new individual.
One of the classes within the phylum Rhodophyta is Charophyta, which includes a group of green algae that are most closely related to land plants. These green algae have some characteristics that are similar to land plants, such as the presence of cellulose cell walls and the ability to photosynthesize using chlorophyll. Charophyta are found in freshwater habitats, such as ponds, lakes, and streams.
Charophyta can be unicellular, colonial, or multicellular in structure. They have a simple body plan, consisting of a single cell or a filament of cells that form branched structures. These algae can reproduce through both sexual and asexual means, with some species producing specialized structures for sexual reproduction, such as antheridia and oogonia.
One of the unique features of Charophyta is the presence of charophycean starch in their cells. Charophycean starch is a type of carbohydrate that is stored in the cell as a reserve energy source. This starch is similar to the starch found in land plants and is thought to be an evolutionary precursor to the starch found in higher plants.
Overall, the phylum Rhodophyta, including the class Charophyta, is a diverse group of algae that play important roles in marine and freshwater ecosystems. Their distinct pigmentation, cell wall composition, and reproductive strategies make them a fascinating group of organisms to study.
References:
1. Graham, L. E., Graham, J. M., Wilcox, L. W. (2009). Algae. Pearson.
2. Guiry, M. D., Guiry, G. M. (2021). AlgaeBase. World-wide electronic publication. National University of Ireland, Galway. http://www.algaebase.org. Accessed on July 15, 2021.
3. Rindi, F., Lam, D. W., López-Bautista, J. M. (2016). Diversity of lower land plants. In MacAllister, C.H., Pais, J. S., Seralvo, L. (Eds.), Advances in botany research (Vol. 82, pp. 209-240). Nova Science Publishers.
4. Round, F. E., Crawford, R. M., Mann, D. G. (1990). The diatoms: Biology and morphology of diatoms. Cambridge University Press.