Study GuideBiology–Protista1. AlgaeAlgaeare a large and diverse group of organisms that can make their own food using photosynthesis.They may beunicellular (single-celled)ormulticellular, and all of them areeukaryotes, meaningtheir cells have a nucleus.Even though algae look plant-like, they arenot classified as plants. They are considered plant-likebecause they containchloroplasts with chlorophyll, which allow them to carry out photosynthesis.Most algae live in theoceans, but many species are also found infreshwater environmentssuch aslakes and ponds.Scientists divide algae into several majordivisions(instead of phyla, which are used for protozoa).These divisions are mainly based on thetypes of pigmentsthe algae contain and theiroverallcolor. The main divisions are:•Rhodophyta•Pyrrophyta•Chrysophyta•Phaeophyta•Chlorophyta1.1Rhodophyta (Red Algae)Rhodophytaincludes thered algae, which are found almost entirely inmarine (saltwater)environments.•Most red algae areunicellular, but some aremulticellular.•Larger forms grow attached to rocks below thelow-tide level, and some are large enough tobe calledseaweeds.•They carry out photosynthesis usingchlorophyll a.Preview Mode
This document has 28 pages. Sign in to access the full document!