Reproduction is a fundamental feature of all known life. Reproduction in macroalgae was only observed in the 18th century, but the ability of microalgae to reproduce sexually was not demonstrated until the 19th century in microscopic green fi lamentous. Structure and reproduction prenticehall biological sciences series by harold charles bold and a great selection of related books, art and collectibles available now at. Asexual reproduction is the production of progeny without the union of cells or nuclear material. Spirogyra species can reproduce both sexually and asexually.
Asexual, or vegetative, reproduction occurs by simple fragmentation of the filaments. Photoautotrophs that produce oxygen except for the water molds, which are funguslike chemoheterotrophs. Some algal species can reproduce by more than one means depending upon the environmental conditions. The pigment used for photosynthesis can even vary, resulting in algae that appear green, red, or brown. Bryophytes onwards in the scale of evolution have the uniform multicellular sex organs, the archegonia, which are not found in algae. It explains the subject in full detail, with special focus on the life cycles of some common genera. Reproduction in algae occurs in both asexual and sexual forms. Writer of the the structure and reproduction of the algae by fe fritsch isvery smart in delivering message through the book.
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. Algae are freeliving, although some can form a symbiotic relationship with other organisms. However, the reproductive structures of some groups of algae e. See all 3 formats and editions hide other formats and editions. Very comprehensive text for physiology algae andor limnology freshwater biology courses at the juniorseniorgrad level. The genus spirogyra comprises more than 300 species and most of them are free floating algae. Filamentous algae are usually considered as macrophytes since they often form floating masses that can be easily harvested, although many consist of microscopic, individual filaments of algal cells. General characters ppt general characteristics of algae ppt what are algae. In addition, algae may occur in moist soil or on the surface of moist rocks and wood. Nostoc belongs to the group cyanophyta of kingdom monera. Most brown algae live in marine environments, where they play an important role both as food and as a potential habitat. Algae lack the various structures that characterize land plants, such as the phyllids leaflike structures of bryophytes, rhizoids in nonvascular plants, and the roots, leaves, and other organs found in.
It is also used as a feed supplement in the aquaculture, aquarium, and poultry industries figure 1. Cyanobacteria structure classification and reproduction. Volvox grows as planktons on surface of water bodies like temporary and permanent ponds, lakes and water tanks. Occurrence, structure and reproduction with diagrams. Fritsch, the structure and reproduction of the algae vol. Spirogyrahabitat, structure, reproduction and germination. Algae live with fungi in lichens according to the whittaker scheme, algae are classified in seven divisions, of which five are. They never produce multicellular embryos inside the female reproductive organ. In addition, it discusses the characteristic features of the important forms of algae, the. Introduction to the algae structure and reproduction. Algae lack a welldefined body, so, structures like roots, stems or leaves are absent.
Green algae include unicellular and colonial flagellates, most with two flagella per cell, as well as various colonial, coccoid, and filamentous forms, along with macroscopic seaweeds, all of which add to the ambiguity of green algae classification since plants are multicellular. Over 10 million scientific documents at your fingertips. Fritsch 194445 classified algae into 11 classes in his book structure and reproduction of. During rainy season due to its fast growth the surface of water bodies become green. Algae guide a case study about the life journey of algae. Sexual reproduction of algae and nonalgal plants uniting gamets of a unicellular alga unicellular gametangia of a filamentous alga multicellular gametangium archegonium liverwort antheridiumantheridium liverwort bold, hc and wynne, mj. Vegetative reproduction occurs through fragmentation, asexual occurs through formation of spores and binary fission, whereas sexual reproduction takes place by fusion of two haploid gametes. Pdf mechanism of sexual reproduction in fresh water microalgae. Nostoc is common as terrestrial and subaerial cyanobacteria. They vary from singlecelled flagellates to simple colonial and filamentous forms. Algae definition, characteristics, types and examples. Phylogeny and molecular evolution of the green algae pdf.
Oclcs webjunction has pulled together information and resources to assist library staff as they consider how to handle coronavirus. Some red algae produce monospores walled, nonflagellate. Spirogyra is a green algae belonging to the class chlorophyceae. Found in freshwater, marine, and moist soil habitats. Baweja p 2006 structure and reproduction of grateloupia lithophila and its. Chara is a fresh water, green alga found submerged in shallow water ponds, tanks, lakes and slow running water. In general, they are considered plantlike, as they are photosynthetic. The word algae refers to a group of organisms that show a great variety in structure and size, ranging from microscopic to over 50 meters in length.
Algae exhibit a wide range of reproductive strategies, from simple asexual cell division to complex forms of sexual reproduction. Numerous and frequentlyupdated resource results are available from this search. Textbook of algae download ebook pdf, epub, tuebl, mobi. There are some stories that are showed in the book. Cambridge university press, london geitler l 1927 rhodospora sordida, nov. Contain chloroplasts which are structures that generate energy for the cell. The following points highlight the three modes of reproduction in algae. Reproduction in algae can be vegetative, asexual, or sexual.
Sexual reproduction occurs by a process known as conjugation, in which cells of two filaments lying side by side are joined by outgrowths called conjugation tubes. Algae also form a component of periphyton, which not only. Of all published articles, the following were the most read within the past 12 months. The structure and reproduction of the algae by fritsch f e. They do not, however, have roots or vessels like plants, and are almost always aquatic. Unicellular algae occur most frequently in water, especially in plankton. Fritsch and a great selection of related books, art and collectibles available now at.
Cyanobacteria structure classification and reproduction is discussed in this article. Download textbook of algae or read online books in pdf, epub, tuebl, and mobi format. Algae algae have been used in animal and human diets since very early times. In the higher form of algae, in addition to vegetative reproduction i. Very comprehensive text for physiology algae andor limn.
In this type, any vegetative part of the thallus develops into new individual. Chlorella and spirullina are unicellular algae, rich in proteins and are used as food supplements even by space travellers. Spirulina, which is a genus of cyanobacteria that is also considered to be a filamentous bluegreen algae, is cultivated around the world and used as a human dietary supplement, as well as a whole food. Variations in cell structure unicellular, colonial, and multicellular. Nostoc structure and reproduction,best animated description. The unicellular algae reproduce mainly by fission or cell division followed by separation of the individual cells. Yellowgreen algae or the xanthophyceae xanthophytes are an important group of heterokont algae. Xanthophyte chloroplasts contain the photosynthetic pigments chlorophyll a, chlorophyll c. Definition, characteristics and structure with diagram.
The structure and reproduction of the algae science. Books can be, and have been, written about each group, but just a few. Most live in fresh water, but some are found in marine and soil habitats. Concepts of botany algae pdf 21p this note contains explanation of algae, structure of alage and its classification. It is widely distributed in alkaline soils, moist rocks, water ponds, streams, and lakes etc. The cyanobacteria are the largest and most diverse group of photosynthetic bacteria. Fritsch, the structure and reproduction of the algae. Reader can get many real examples that can be great knowledge. Many small algae reproduce asexually by ordinary cell division or by fragmentation, whereas larger algae reproduce by spores.
Algae regenerate by sexual reproduction, involving male and female gametes sex cells, by asexual reproduction, or by both ways. Algae dont have vascular tissues non vascular plants. The structure and reproduction of the algae volume 1 by f. Fritsch 194445 classified algae into 11 classes in his book structure and reproduction of algae based on the following characteristics. Types of reproduction there are three common methods of reproduction found in algae. Reliable information about the coronavirus covid19 is available from the world health organization current situation, international travel. For instance, macrocystis, a kelp of the order laminariales, may reach 60 m 200 ft. Fritsch fe 1935 the structure and reproduction of algae, vol i. Algae lack the roots, stems, leaves, and other structures typical of true plants. Chlorophyta is a division of green algae contain chlorophylls a and b, and store food as starch. The volvox colonies appear as green rolling balls on surface of water. Many small algae reproduce asexually by ordinary cell division or by fragmentation, whereas larger algae reproduce by.