Although most protozoa reproduce by asexual methods, sexual reproduction has been observed in. They possesses brown colored photosynthetic pigments fucoxanthin and. Definition, characteristics and structure with diagram. They are chlorophyllous thus autotrophic, with simple thallus and lacks tissue differentiation. Algae can be either unicellular or multicellular organisms. Classes prasinophyceae chlorophyceae evolutionary lines flagellated species nonflagellated species colonies filaments ulvophyceae charophyceae phylum chlorophyta general characteristics. They grow attached to the rocks, shells, or coarser algae such as the kelps. They are a multicellular, filament, blade structure.
In most groups of algae it appears that the plastid has been derived by at least two serial endosymbioses. The thallus of algae shows great degree of variation in size and form. Red algae is an nonvascular plant that doesnt have a tube that produces water to its stem. The word algae represent a large group of different organisms from different phylogenetic groups, representing many taxonomic divisions. Thallus diversity, reproduction and life cycle of algae. They form a vital part of the food chain and are also involved in producing about 40 to 60 per cent of the total global oxygen for both terrestrial habitat and other aquatic habitats. Algae definition, characteristics, types and examples byjus. General characteristics of algae with key points easy. They are chlorophyllous thus autotrophic, with simple. Algae are chlorophyllbearing autotrophic thalloid plant body. Algae definition, characteristics, types and examples. In large, macroscopic algae, groups of cells are specialized for specific functions, such as anchorage, transport, photosynthesis, and reproduction. Red algae general characteristics and uses of red algae. General characteristics of algae, classification of algae based on habitat, thallus diversity in algae, chloroplast shape variations in algae, pigmentation in algae, reproduction in algae, life cycle in algae.
Ranging from microscopic to walnutsized, masses of nostoc may be found on soil and floating in quiet water. Kingdom protista land plants evolve recentplants, 500 mya division phaeophyta, first brown plants standard eukaryote cells motile cells usual no multinucleate cells nonstandard chloroplasts general features defining characteristics. Domain eukaryote group plantae division phyta chlorophyta class phyceae ulvophyceae order ales ulvales. Nostoc, genus of bluegreen algae with cells arranged in beadlike chains that are grouped together in a gelatinous mass. They occur both in marine and fresh water habitats. General characteristics of algae definition, examples. In a superficial sense, these organisms are often described based on their similarities to the other groups of eukaryotes. They usually lack the capability for photosynthesis, although the genus euglena is renowned for motility as well as photosynthesis and is therefore considered both an alga and a protozoan.
Algae are simple,unicellular,nonjacked sex organ and have no embryo development. The following sections discuss the characteristics and use of both true algae and the cyanophyta, hereinafter referred to as bluegreen algae. Algae is the term given to a large and diverse group of organisms that tend to be found in watery areas. Higher fungi like ascomycotina and basidiomycotina. The life of the planet began the long, slow process of modulating and regulating the physical conditions of the planet. Algae algae physical and ecological features of algae. Algae a ubiquitous and diverse group ranges from unicellular to giant multicellular forms. Unlike green algae or chlorophyta, they lack true starch. General characteristics of algae algae are eukaryotic organisms that have no roots, stems, or leaves but do have chlorophyll and other pigments for carrying out photosynthesis. General types of septa types of septa based on their formation. The food reserves contain sugar, higher alcohol and other complex forms of polysaccharides. Included organisms range from unicellular microalgae, such as chlorella and the diatoms, to multicellular forms, such as the giant kelp, a large brown alga which may grow. A special thickwalled cell akinete has the ability to withstand desiccation for long periods of time. Spirulina algae arthrospira platensis is a bluegreen microalgae with a spiral shape that grows spontaneously in few areas of the world, such as mexico or africa, where the water of the lakes has a high alkalinity, the temperatures remain constant between 30c degrees and 40c degrees and there is a high concentration of mineral salts.
Many algae consist of only one cell, while the largest have millions of cells. Chlorophyta is a division of green algae contain chlorophylls a and b, and store food as starch in their plastids. This quizworksheet combo will help you test your understanding of the characteristics of. Algae exhibit a very wide range of morphological diversity. General characters with power point presentation ppt.
Sepro research and technology campus, 160 watson seed farm rd. They show biphasic or triphasic life cycle patterns. Learn vocabulary, terms, and more with flashcards, games, and other study tools. In contrast to the land plants, algae have very diverse mechanisms of photosynthesis, and especially of light harvesting pigments and assemblages. However, there are some common characteristics across species. A single endosymbiosis appears to have occurred in the green algae, the red algae and the glaucocystophytes. Algaegeneral characteristics and classification online biology. Characteristics of algae with diagram biology discussion. Some of the algae are also found as terrestrial, subterranean or epiphytic forms. General characteristics and structures this clade is identified by cell walls made up of overlapping silica tests called a frustule. The algae and their general characteristics springerlink.
Request pdf general characteristics of algae algae a ubiquitous and diverse group ranges from unicellular to giant multicellular forms. Protozoa are notable for their ability to move independently, a characteristic found in the majority of species. There are many different species belonging to chlorophyta. In general, the brown algae flourish in colder ocean. The cell walls are composed of cellulose and alginic acid a complex polysaccharide. When motile volvox, chlamydomonas the cells are generally provided with a pair of eukaryotic flagella. Motile or nonmotile algae may form a colony, known as a coenobium. The major groups of algae are therefore related to the type of protist host and the type of plastid, and these are described. For instance, algae can photosynthesize like plants. They are thallophytes which have chlorophyll as their primary photosynthetic pigment and lack a sterile covering of cells around the reproductive cells. Cyanobacteria and oxygen cyanobacteria release oxygen through photosynthesis only producers of oxygen over several hundreds million years in the biosphere.
They may be spherical protococcus, chlorella, or pyriform chlamydomonas. Algae physical and ecological features of algae britannica. Algae are eukaryotic, autotrophic and usually aquatic thallophytes. Algaegeneral characteristics and classification online. The genome structures within chlorophyta are all different. It is an alga rich in vegetal proteins very useful for. Learn introduction to algae from university of california san diego. Primary septa are formed in direct association with nuclear division mitotic or meiotic and are laid down between daughter nuclei separating the nuclei cells. The term algae latin seaweeds was first introduced by linnaeus in 1753, meaning the hepaticeae. The algae comprise of a large heterogeneous assemblage of. General characteristics of algae request pdf researchgate.
Algae lack a welldefined body, so, structures like roots, stems or leaves are absent. The term thallus is used for a plant body that is not differentiated into root stem and leaves and lacks vascular system. The oxygen in todays atmosphere is almost entirely the result of photosynthetic living, which had its start with the appearance of bluegreen algae among. Bluegreen algae cyanobacteria not an a at all snowella species. Specific general characteristics of algae are common to plants as well as animals. Phaeophyta characteristics of phaeophyta the members of this division are commonly called brown algae because of dominant carotene and fucoxanthin, the brown algae are widespread and with few exceptions all are marine. Algae are eukaryotic organisms that have no roots, stems, or leaves but do have chlorophyll and other pigments for carrying out photosynthesis. In addition, algae may occur in moist soil or on the surface of moist rocks and wood. In general algae can be referred to as plantlike organisms that are usually photosynthetic and aquatic, but do not have true roots, stems, leaves, vascular tissue and have simple reproductive structures. The simplest forms are unicellular, microscopic, motile or nonmotile eukaryotic cells. Algae have simple, unicellular nonjacketed sex organs and have no embryo development. Phaeophyta characteristics phaeophyta are the most complex forms of algae.
The kingdom protista consists of eukaryotic protists. Classes in detail 2 hierarchical system of classification. Listed below are general characteristics of red algae. In general, higher concentrations of nanoscale materials show adverse effects on plants and algae, can damage their photosynthetic apparatus, inhibit photosynthetic electron transport or co2. As algae possess chlorophyll, they are photosynthetic in nature. Algaegeneral characteristics, classification, organization of thallus, cell structure. They are found in different habitats from fresh to marine waters to extreme conditions. The very common fresh water algae are chlamydomonas, volvox, ulothrix, chara, oedogonium, spirogyra, nostoc, oscillatoria etc. We also acknowledge previous national science foundation support under grant numbers 1246120, 1525057. Algae live with fungi in lichens according to the whittaker scheme, algae are classified in seven divisions, of which five are.
The size range of the algae spans seven orders of magnitude. The autotrophic cyanobacteria were once classified as blue green algae because of their superficial resemblance to eukaryotic green algae. Biogeography the diatoms are unicellular algae that are a large component of phytoplankton in oceans and lakes. Cyanobacteria played a crucial role in the evolution of all photosynthetic plants and algae in existence today.
Diatoms show a characteristic type of nonflagellar locomotion. Unit 8lesson 5 characteristics of algae flashcards quizlet. Listed below are some of the general characteristics of algae. For instance, algae can photosynthesize like plants, and they possess specialized structures and cellorganelles, like centrioles and flagella, found only in animals. Characteristics of algae presentation by ali akbar,hassan adrees,rida ayoub,tanzila ashraf maria nasrullah gc university faisalabad punjab,pakistan 2.
This course was produced by the algae technology educational consortium and uc san diego with funding from the algae foundation, the national renewable energy lab, and the u. General characteristics of phaeophyceae pheophyceae are called commonly known as brown algae photosynthetic pigments. The study of algae is known as phycology phycos seaweed. In this article we will discuss about the morphological and cellular characteristics of algae. Members of this very diverse kingdom are typically unicelluar and less complex in structure than other eukaryotes. Unicellular algae occur most frequently in water, especially in plankton. Algae are used as food as they are rich in carbohydrates, vitamins and few other inorganic substances.
Start studying unit 8lesson 5 characteristics of algae. The general characters characteristics of algae ppt. Botany syllabus unit1 algaegeneral characteristics. The members of phaeophyta belonging to laminarales are called kelps.