BISC 120Lg Study Guide - Midterm Guide: Excavata, Polyphyly, Heterotroph

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Eukaryotes that are not plants, animals, or fungi. Mostly unicellular eukaryotes but can also be multicellular: polyphyletic group. Nutritionally diverse: photoautotrophs: contain chloroplasts, heterotrophs: absorb organic molecules or ingest larger particles, mixotrophs: combine photosynthesis and heterotrophic nutrition. Can reproduce sexually or asexually: used to be thought that amitochondriates (lacking mitochondria) were the oldest lineage of eukaryotes, but have sense been reclassified. After a diatom bloom, many dead individuals fall to the ocean floor where decomposition is slow. Algal blooms: often caused by lingulodinium, releases toxins, but it"s energetically expensive, toxins can inhibit/kill other phytoplankton, form of interspecific competition. Some of the cells dry up after forming a stalk that supports an asexual fruiting body: other cells crawl up the stalk and develop into spores, spores are released, and the goal is dispersal. Essential for the well-being of most terrestrial ecosystems because they break down organic material and recycle vital nutrients.