KON Unit-4 Lab

Unit #4 Lab: Photosynthetic bacteria, Protist and Fungi Learning objectives: 1. Familiarize with different divisions of photosynthetic organisms by using the representative members of each one. 2. Compare and contrast major divisions of algae. 3. Observe representative organisms classified within the kingdom Fungi 4. Identify morphological structures characteristic for different phyla of Fungi 5. Compare and contrast different reproduction strategies for different phyla of Fungi PART A: PHOTOSYNTHETIC BACTERIA AND PROTISTS I NTRODUCTION Cyanobacteria and algae are photosynthetic organisms that, because of their physiological and ecological affinities, had been grouped in the distant past as divisions of the plant kingdom. However, newly acquired knowledge of the cell biology, genetics and biochemistry of the groups clumped as algae has led to an overhaul of their classification. Cyanobacteria ( blue-green algae) is part of the eubacteria . This decision is a reflection of the prokaryotic nature of the cellular organization, physiology, biochemistry, and reproductive means of these microorganisms. Most C yanobacteria are aquatic, a few species are terrestrial and some cyanobacteria are in symbiosis with invertebrate animals. It is important to note that algae and cyanobacteria are so similar from an ecophysiological standpoint that both groups are capable of entering in symbiotic relationships with fungi to form lichens . Algae is a common name which describes a very diverse group of eukaryotic organisms that have been placed within the Protista . Despite photosynthetic capacity and their multicellularity, algae differ from higher plants in their lack of well-organized tissues and in their reproductive mechanisms. Current classification of eukaryotic organisms and photosynthetic organisms amongst them with the respect to modern phylogenetic data is represented on Fig. 1. Currently, eukaryotes are divided into four supergroups: Excavata, SAR, Archaeplastida and Unikonta, with algae distributed in all of them except Unikonta. Algae are quite diverse in a wide variety of aspects. The size of algae range from microscopic to macroscopic, with some kelps, or brown algae, reaching up to 40-50 m in length. Habitats occupied by algae are generally aquatic, with varying ranges of salinity, but there are some terrestrial groups, in soil, and on the surfaces of many objects. Some algae live in extreme temperatures, in places such as hot springs or permanent patches of snow. They also differ anatomically, cytologically, biochemically, and in the types of life cycles. The purpose of this lab is to familiarize you with several groups of algae by using representative members of each one. Keep in mind that, as knowledge about living organisms grows, new and better phylogeny and classification systems are established. 1

CYANOBACTERIA: Oscillatoria , Nostoc, and Anabaena are representative species for this group of algae (Fig. 2). Oscillatoria is a long filamentous cyanobacterium that moves by means of a gliding motion. The cells of Oscillatoria form filaments, but the cells are not dependent on one another for survival. Every cell is functionally the same. Nostoc is a cyanobacterial genus that typically forms gelatinous balls which can either float free in the Figure 1. Modern classification of eukaryotic organisms with respect to current phylogenetic data. Photosynthetic organisms covered in this lab are circled with a dashed line. 2

PROTISTS (ALGAE): Algae (common name) or Protists belong to the Kingdom Protista as the organisms belong to this groups are not plants, not animals or even fungi. We will learn about the organisms belong the Kingdom Protista on the basis of their pigmentation, habitat, morphology, unicellular or multicellular and their unique reproductive structures. In this lab exercise you will also learn about algae also on the basis of phylogenetic evidence as super group. (i) Supergroup Excavata Clade Euglenozoa Euglena (Fig. 3A) represent this group of flagellate mixotrophic protozoa . As all Excavata, they have a unique flagella and an “excavated” feeding groove. Their cells can change shape as they swim. Euglena also has a gullet, chloroplasts, eyespot and paramylum, where they reserve food. When grown in the dark, the chloroplasts in Euglena do not develop and cells are not green. In this case Euglena becomes a heterotroph, it surrounds a particle of food and consumes it by phagocytosis. That's why Euglena is also a mixotroph. Q. Under 100 x magnification you can see an orange pigment in Euglena what is the name of that pigment? What is it function? __________________________________ (ii) Supergroup SAR This supergroup is one of the most controversial groups out of the four. Within this supergroup, algae can be found in clades Alveolata and Stramenopila. - Clade Alveolates Dinoflagellates – Dinoflagellata Dinoflagellates have the cell wall and the two flagella. One lies in a groove around the waist or cingulim and undergoes undulating movements while the other projects forward from the logitudinal groove or sulcus for locomotion. As all other members of Alveolates clade, they have membrane-enclosed sacs (alveoli) just under the plasma membrane. Click on the video link to find out the live view of Dinoflagellate https://youtu.be/49SQMspNsoA Figure 4. Euglena under 40 x and 100 x magnification Reference source: https://www.algaebase.org/search/pictures/ 4

Q. Label the grove in the 100x magnified view of Peridinuim . ____________ Dinoflagellates are the organisms responsible for “red tides,” which are blooms or overgrowth of these organisms. Because red-tide dinoflagellates produce toxins, blooms can result in widespread destruction of fish. Many dinoflagellates are also luminescent like Noctiluca scintillans . - Clade Stramenopiles Stramenopiles clade includes some of the most important photosynthetic organisms on Earth. Most of them have a “hairy” flagellum paired with a “smooth” flagellum. Brown algae The brown algae are mainly marine. The brown color is due to a carbohydrate, laminarin . The kelps, such as Laminaria may be many meters long and can be found in the Pacific Ocean. Fucus is another common brown alga which contains air vesicles and special reproductive structures at the tips called receptacles. Click on the link https://www.algaebase.org/search/images/ and download the image of Laminaria Q. What is the name of the specialized structure, which holds the entire thallus to the ocean floor. Download the image using the link above. Diatoms –Bacillariophyceae Cell walls of Diatoms (Fig. 6) are composed of silicon dioxide (similar to glass), and consist of two separate parts (or valves) similar to a petri dish. Note the variety of form. Diatoms are divided into two types on the basis of symmetry. The first group, the pennate diatoms, is characterized by its bilateral symmetry. The second group, or the centric diatoms , possesses radial symmetry. Diatoms are perhaps economically the most important of the algae because of their role in the food cycle of Figure 5: Peridinium (40x and 100x) 5

4. One class of the Chlorophyta, the charaphycean green algae, have members that undergo cytokinesis, like plants, through the creation of a cell plate mediated by a phragmoplast. The green algae exhibit a great morphological diversity. During this lab you will examine representative green algae exemplifying several types of morphological structure ( thallus ), or organization of body shape and size. These are: a) Unicellular: Chalmydomonas. b) Filamentous: Stigeoclonium, Odeogonium, Bulbochaete Stigeoclonium and Odeogonium have a filamentous form. Bulbochaete generally grows on other algae; it has a bulb-shaped terminal cell. a) Colonial: Volvox. Volvox This impressive algae again consists of colonies of Chlamydomonas-like cells. In this case, however, each colony includes over 500 cells. b) Tissue-like: Ulvophyceae – marine macroalgae (seaweeds). Membranous: Ulva. Ulva is often referred to as “sea-lettuce”. It is a genus of edible green algae that is widely distributed along the coasts of the world's oceans. In this lab you will learn green algae in two groups: Chlorophytes and Charophytes Clade Chlorophyta We will use this link to learn about the different types of chlorophyta: http://botit.botany.wisc.edu/Resources/Botany/Chlorophyta/ (1) Chlamydomonas – Click on the above link and open the image folder with Chlamydomonas download image with pyrinoids.  What is the shape of the chloroplast?_____________  Where you will locate the pyrinoid?_________________  Using your downloaded image label the flagella, chloroplast and pyrinoid. (2) Oedogonium – Click on the above link and open the image folder with Oedogonium . Feel free to explore all image.  What kind of green algae Oedogonium is? ________________________  What is oogonium?______________________________  How will you differentiate the filament with antheridium and oogonium?_____________________ (3) Ulva – Click on the habitat image, download and label the holdfast and thallus.  Is Ulva a macroscopic or microscopic algae? ___________________________  What is the common name of Ulva?__________________________________ (4) Volvox – Use the above link and observe the colonial structure of Volvox .  How the maternal and daughter cells are hold together in Volvox ?______________________  List some major morphological differences between Chlamydomonas and Volvox 7

__________________________ _________________________ _________________________ _______________________________ Clade Charophyta Charophyta, or stoneworts , are green algae that have a filamentous or tissue-like thallus and a very complex (but still single cellular!) reproductive structures. They contain sporopollenin in the cell walls and are considered the closest group to the land plants. The individual cells may be several millimeters long. They are thus widely used for the study of protoplasm, vacuolar contents and cytoplasmic streaming. Cosmarium, Clostridium , Spirogyra , Chara and Nitella represent Charophyta. In this lab our specimens are Spirogyra (microscopic) and Chara (macroscopic) algae. (1) Click on this link : http://botit.botany.wisc.edu/Resources/Botany/Chlorophyta/Spirogyra/ and download image of vegetative structure and conjugation.  Spirogyra has unique chloroplast. What is the shape of the chloroplast in Spirogyra ? _____________________________ Download and label the image with conjugation using the above link with Spirogyra : male filament, female filament and zygotes? (2) Using the link http://botit.botany.wisc.edu/Resources/Botany/Chlorophyta/Chara/ to view the specimen Chara . Do you find tissues in the thallus? List some unique features of Chara thallus distinct than other algae? 8

3. Why could Euglena be classified both as a plant and an animal? 4. What is the cell wall of cyanobacteria or algae made of? What about Diatoms? GROCERY STORE BOTANY Make a trip to your nearby Grocery Store and look for products that contains algae in the ingredient list. Take picture, write the name of the product and which component is from algae and submit along with the lab worksheet PART B: FUNGI Fungi (singular, fungus ) are eukaryotic organisms that visually resemble algae and plants in that their cells have cell walls that make them relatively rigid, as opposed to animal cells, which do not have cell walls and are more flexible. However, fungi and animals are both heterotrophs (they obtain their food from other organisms), while most plants and algae are autotrophs (they can make their own food from inorganic molecules). Unlike animals, fungi do not ingest their food but rather obtain food by absorption . Fungi live either as saprophytes, parasites, or in mutualistic partnerships. Fungi have cell walls made of chitin and, with the exception of some unicellular species. Fungal cell structure In most fungi, the cells are organized into a branching system of long tubes surrounded by cell walls, the hyphae (singular, hypha ). The hyphae grow at their tips, except where they produce side branches. The hyphae form a network-like tissue named a mycelium (plural, mycelia ). Hyphal growth enables the fungi to spread through long distances in the soil and to grow inside solid materials that contain food (for example, wood, fruits, and bread, which are thus spoiled by fungi: they become moldy). The mycelium is a vegetative part of the fungus: it grows and takes up nutrients from the medium in which the fungus grows. Because of the rigid cell wall, the fungus cannot take in nutrients in solid or particulate form, but only absorb them in soluble form. The mycelium has a vast surface area from which it can secrete digestive enzymes that break down solid food into small, soluble molecules that can then be absorbed through this surface. 10

Life cycle Fungi can reproduce either sexually or asexually (Fig. 9). In asexual reproduction, asexual spores are genetically identical to the parent, produced by mitosis and may be released either outside or within a special reproductive sac called a sporangium (plural: sporangia ). After a certain period of growth, the hyphae bear large numbers of haploid spores that can remain dormant for long periods of time. The spores neither grow nor feed, but are responsible for dispersal, typically by air or water. Spores that reach a favorable substrate will germinate to form a new mycelium. Spores are often generated on special hyphae or in complex fruiting bodies (for example, mushrooms), formed by many entangled hyphae. Spores are also resistant to harsh conditions that are not suitable for mycelium survival, such as extreme temperatures or lack of moisture. Some fungi can asexually reproduce by budding. Sexual reproduction in fungi usually involves: 1. Plasmogamy , the fusion of the cytoplasm (but not of the nuclei) of hyphae from two haploid mycelia of different mating types, forming a heterokaryotic mycelium in which each cell has two nuclei of different mating types (this is a unique reproductive stage, found only in fungi !), 2. Karyogamy – the fusion of the two parental nuclei, which may happen after a long period of growth of the heterokaryotic mycelium, forming a diploid zygote (the zygote is the only diploid stage in fungi!), and 3. Direct meiosis of the zygote, resulting in the formation of haploid sexual spores which can germinate into new mycelium. Figure 9. Generalized lifecycle of Fungus. 11

Ascomycetes : Clink on this link and open the folder with Peziza . http://botit.botany.wisc.edu/Resources/Botany/Fungi/Ascomycota/Peziza/ Click on the above link on Peziza and answer the following questions:  What is the colour and shape of fruiting body of Peziza.______________________  How to find out which one is the ascospore in Peziza apothecium?______________  You found the your orange in the bag is covered with lots of mold. What kind of fungus you think it will be? The colour is due to the spores or due to hyphae? ______________________________________________________________________ __________________________________________________________________ To learn more this fungal phylum look carefully at each specimen given in the link folder http://botit.botany.wisc.edu/Resources/Botany/Fungi/Ascomycota/ Basidiomycetes: Basidiomycetes are also known as club fungi. All mushrooms are basidimycetes. http://botit.botany.wisc.edu/Resources/Botany/Fungi/Basidiomycota/Agaricus%20&%20Coprinus/  Get a mushroom and observe using the link above. The edible part of mushrooms is a _________________  Label the different structures of a mushroom given in Fig. 12  Where you will find the spores? ____________________________  Other than edible mushrooms, what are the other fungi belong to this Phylum? Lichens : In nature lichens are available with three growth forms. Click on the link to learn about lichens: http://botit.botany.wisc.edu/Resources/Botany/Fungi/Lichens/Habit %20Images/  Write their names:_______________________________ Figure 12 Figure 12 13

 A lichen thallus is a symbiotic association of two organisms which are__________________&__________  What is the economic importance of lichens?______________________ ___________________________________________________________________________ References and Resources:  http://botit.botany.wisc.edu/Resources/Botany  http://www.seaweed.ie/descriptions  https://plants.sc.egov.usda.gov  https://www.algaebase.org/search/pictures/  American Museum of Natural History  Customized Lab Manual for BIO2500 14