- Why are seaweeds assigned to the Protista rather than Plantae? Seaweed is a protist. Unlike plants, seaweed does not have a complex root and shoot system or specialized tissues to move water and nutrients. It can absorb water and nutrients through any tissue. Seaweed can also photosynthesize in all of its tissues rather than just the leaves.
- List, describe, and state the function of the four basic parts of a seaweed. Also, state the name for the entire seaweed body. There were several primary symbioses between eukaryotes and blue green algae. In one lineage, the photosynthetic organism lost much of its genetic independence and became functionally and genetically integrated as chloroplasts within the host cell. Modern chloroplasts, also called plastids, are bounded by two or more membranes, and most usually lie free in the cytoplasm.
- What are the most important ecological roles filled by seaweeds? Seaweeds play very important ecological roles in many marine communities. They are a food source for marine animals such as sea urchins and fishes, and are the nutritional base of some food webs. They also provide shelter and a home for numerous fishes, invertebrates, birds, and mammals.
- List several types of environmental stress seaweeds encounter. These primary influences act with others to change marine plant biodiversity, which includes the number of marine species, their abundances and their genetics. In turn, marine plant biodiversity is known to influence ecosystem functions, such as food web support and mineral cycles.
- Briefly describe sexual and asexual reproduction in seaweed. Seaweeds reproduce in a variety of ways. Lower types reproduce asexually. More advanced kinds produce motile zoospores that swim off, anchor themselves, and grow into new individuals, or they reproduce sexually by forming sex cells (gametes) that, after fusing, follow the same pattern. Sometimes pieces of a seaweed break off and form new plants; in a few species there is a cycle of asexual and sexual reproduction foreshadowing the alternation of generations characteristic of plants.
- Upon what characteristic are seaweeds classified? Seaweeds are classified into three major groups; the green algae, the brown algae, and the red algae. Placement of seaweed into one of these groups is based on the pigments and colouration existing in the plant. Other seaweed features that are used to classify algae include: cell wall composition, reproductive characteristics, and the chemical nature of the photosynthetic products. Plant structure, form and shape are additional characteristics used to classify seaweed.
ALgan and Fucans
ranges from single-celled forms to multi-cellular sheets, and branched filaments
chlorophyll, phycocyanin and phycoerythri
Cold oceanic waters
Only about 10% of green algae are marine species, most live in freshwater.
food, cosmetics, pharmaceuticals and in the sciences.