Algae Tutorial Materials

ALGAE Algae are eukaryotic and generally in nature photosynthetic with pigments green (chlorophyll), brown (phycoxanthin), blue greenish (phycobilin), and red (phycoerythrin). Algae Habitat Algae can live on the surface or in water (aquatic) and land (terrestrial) exposed to sunlight. It can live on the surface of soil, logs and other. It also can form symbiosis with fungi and form lichens. Lichenes can form by algae that are members of Chlorophyta, Xanthophyta, and blue green algae (Cyanobacteria) are included bacteria. Phycobionts used sunlight for photosynthesis, it make an organic material is produced that can be utilized by mycobionts while mycobionts provides protection and functions to absorb minerals phycobiont. In some cases mycobionts can produce growth factors which can be utilized by phycobionts. Lichens are very slow growth but can live in extreme places where it cannot used as a place for other living bodies to grow. The extreme places that mention before such lichenes can grow on rocks in very dry, hot and dry conditions poor in nutrients or organic matter. Algae Morphology Unicellular (microscopic) algae can actually be single cells, or grow in the form of chains or filaments. Algae can seen with naked eye (macroscopic) if they are form colonies like volvox which formed colonies from 500-600 cells. Some types of algae have similar structures called hold fast which is similar to the root system in plants, which functions to attach algae to certain rocks or substrates, but cannot be used to absorb water or nutrients. Algae does not require nutrient and water transport system, because nutrients and water can be met from all algae cells. Another special structure is the bladder or float, which is useful for placing algae in the right position to obtain maximum light. The stalks or stems on algae are called stipes, which are useful to support the blade, which is the main part of the algae that functions to absorb nutrients and light. Algae Growth Whereas In eukaryotic algae, chromosome doubling occurs in a more complex process complex called mitosis. Each cell is the result of division have derivative chromosomes. Other algae, especially multicellular ones, thrive in many ways. Some types of algae can carry out fragmentation, namely cutting of parts of the filament that can then grow into individuals new. Other algae reproduce by producing spores. Algae spores have a different structure from endospores in bacteria. Spores are present those that can move actively are called zoospores, and those that cannot actively moving (nonmotile) are called autospores.Asexual reproduction in algae such as in corpses other eukaryotes, namely by the formation of two types of special cells called haploid gametes. The two gamete cells fuse and produce The zygote is diploid. Zygotes have two derivatives each chromosome (2n). Gametes only have one chromosome derivative (1n). Process This reduction in the number of chromosomes is called meiosis. Algae Physiology In general, algae are photosynthetic, using H2O as energy electron donor, under certain circumstances some algae can use H2 for the process of photosynthesis without producing O2. Some algae are chemoorganotrophs so that it can catabolize simple sugars or organic acids in dark condition. The organic compounds that are widely used by algae are acetate which can be used as a C source and energy source. Certain algae can assimilate simple organic compounds using energy sources light (photoheterotrophs). In certain algae the process may not occur photosynthesis at all so in this case nutritional needs are met heterotrophically.