1 Sylvia S Mader Immagini e concetti della

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Sylvia S. Mader Immagini e concetti della biologia 2 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

A 10 - Protists, plants and fungi 3 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Protista Protists contain membrane-bounded organelles as mitochondria and chloroplasts. Endosymbiosis theory: as mitochondria and chloroplasts have their own DNA, they may have derived from the symbiosis of an aerobic bacteria (or cyanobacteria) engulfed by a primitive prokaryotic cell. 4 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Protista Protists include very diverse organisms 5 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Protista Protists are diverse in cellular organization, nutrition strategy, reproduction and locomotion. Considering the nutrition strategies, Protists are divided into four groups. • Protozoan and slime molds: heterotrophic by ingestion (endocytosis) or parasitic. • Water molds: heterotrophic by absorption or parasitic. • Algae: photosynthetic. 6 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Protista: Protozoan are protists with animal-like behavior heterotrophic strategy and movement: • Zooflagellates • Euglenoids • Amoeboids • Foraminiferans and Radiolarians • Ciliates • Sporozoan 7 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Protista: Protozoan Zooflagellates Move by flagella and are parasitic (some of them can cause diseases to humans). Euglenoids Move by flagella, are flexible and often contain chloroplasts. Live in fresh waters. Amoeboids Move and ingest by pseudopods, bulges of the cytoplasm. In salt water compose the zooplankton. 8 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Protista: Protozoan Foraminiferans and Radiolarians Produce a test (or shell) in calcium carbonate and silicon respectively. Dead Foraminiferans and Radiolarians compose the rocks of the ocean floors. Ciliates Move by cilia and reproduce both sexually (binary fission) and asexually (conjugation). Sporozoans Are not motile. They are parasitic and form spores as i. e. the Plasmodium, causing Malaria. 9 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Protista: Slime molds Plasmodial slime molds Phagocytize decomposing plant material in forests and agricultural fields. Cellular slime molds Microscopic protists that exist as individual amoeboid cells. 10 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Protista: Water molds More than 500 species inhabiting mainly aquatic environments and feeding on dead fish and insects (saprophyte). 11 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Protista: Algae Diatoms Are a major group of unicellular algae inhabiting fresh and salt water and are one of the most common types of phytoplankton. Have a unique cell wall made of silicon called a frustule. Cyclotella Dinoflagellates Marine producers, as diatoms, and have a cell wall made of cellulose plates and silica with two flagella. Cellulose plates Flagella 12 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Protista: Algae Red and brown algae Are multicellular complex protists and are the largest groups of eukaryotic algae. Are commonly used in pharmacy and as an important source of food. Chondrus crispus, red algae Fucus, brown algae 13 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Protista: Algae Green algae have diverse forms, from flagellated unicellular to filamentous colonial and multicellular. Green algae photosynthesize as plants but they cannot reproduce on land. Volvox, colonial Ulva, multicellular 14 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Protista: Algae Green algae life cycle has many variations: haploid, with alternation of generations or diploid. 15 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Plantae 16 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Plantae Fossil records show that plants evolved from fresh water green algae. Evidences: • Both plants and green algae have type a and type b chlorophylls • Both plants and green algae store carbohydrates as starch • Both plants and green algae have cellulose in the cell wall 17 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Plantae Derived characters 1. The embryo is protected within the plant body 2. Developed vascular tissue 3. Seed 4. Evolution of the flower 18 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Plants evolution 19 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Plants have alternation of generations Sporophyte Diploid (2 n) generation, it produces haploid spores by meiosis. Gametophyte Haploid (n) generation, it produces gametes (eggs and sperms) by mitosis. 20 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Plants have alternation of generations During evolution, the sporophyte became dominant over the gametophyte as plants adapted to life on land. 21 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Bryophytes: non vascular plants Low-lying non vascular plants Antheridium is the organ producing male gametes. Archegonium is the organ producing female gametes. 22 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Bryophytes: nonvascular plants • The dependent sporophyte produces windblown spores • The dominant gametophyte produces water-swimming flagellated sperms 23 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Pteridophytes: ferns and their allies Moderate size, seedless vascular plants that prefer moist locations. Leaves are called fronds and can be divided into small leaflets. 24 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Pteridophytes: ferns and their allies • The dominant sporophyte produces windblown spores • The independent and separate gametophyte produces water-swimming flagellated sperms 25 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Gymnosperms: naked seeds Large cone bearing seeds plants that form big tree forests. This group includes Cycads, Ginkgoes, Gnetophytes and Conifers (evergreen trees). 26 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Gymnosperms: naked seeds • Dominant sporophyte produces pollen cones and seed cones • Pollen cones produce windblown pollen (male gametophyte) • Seed cones bear ovules which develop into naked seeds 27 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Carboniferous forests 300 MA ago a great swamp forest encompassed the actual Europe, Ukraine, and USA. The partially decomposed remains of those trees were covered by swamp sediments that became sedimentary rocks. This organic matter formed big deposits of the coal we use today as fossil fuel. 28 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Angiosperms: flowering plants Angiosperms where the last plants to evolve during Cenozoic era (bout 65 MA ago) in coevolution with flying insects (pollinators). Plants of all sizes, living in all habitats. • Dominant sporophyte bears flowers which produce pollen grains (male gametophyte) and enclose ovules (female gametophyte) within an ovary. • Ovules become seeds that protect a sporophyte embryo. • Fruits develop from ovary. Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012 29

Angiosperms: flowering plants Flowering plants are divided into two main structural systems: 1. Shoot system (include stems, leaves and flowers); 2. Root system (primary root and root hairs). 30 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Angiosperms: flowering plants Stem is divided into nodes and internodes. It supports leaves and transports fluids between the roots and the shoots (vascular system). Leaves carry on photosynthesis. 31 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Angiosperms: flowering plants Roots anchor the plant, absorb water and nutrients from the ground and can store water and other plant products. 32 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Angiosperm derived characters The flowers, are the reproductive organs of angiosperms and distinguish them from other plants. Protect the ovary Attract specific pollinators Protect the flower before blooming 33 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Angiosperm derived characters The stamen, is the pollen-producing reproductive organ of a flower. Stamens have contributed to the diversification of angiosperms with adaptations to specialized pollinators. Anther Filament 34 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Angiosperm derived characters Monocotyledons and Cotyledons 35 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Angiosperms life cycle 36 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Plants absorb CO 2 and free O 2 37 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Plants requires minerals Minerals are inorganic substances (ions or compounds) that can be transformed by plants into organic molecules. 38 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Fungi 39 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Fungi: heterotrophic and saprophytic Fungi play are important in nutrient cycling as they decompose, especially as saprotrophs and symbionts, degrading organic matter to inorganic molecules for plants. The fungal body is made up by filaments and hyphae interconnected in a network called mycelium Fungal cells contain chitin and glycogen. 40 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Fungi life cycle Fungi produce windblown spores during both sexual and asexual reproduction. 41 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Fungi are divided into three main groups, depending on the reproductive organs: 1. Zygomycota (black bread mold) have zygospores; 2. Ascomycota (sac fungi and yeasts) have an ascus; 3. Basidiomycota (mushrooms) have a basidium. 42 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012

Kingdom Fungi have mutualistic relations with algae and plants. Lichen is a symbiotic association between a fungus and a cyanobacteria or a green algae. Mycorrhizal fungi form association with plants roots, increasing the nutrient absorption surface. 43 Sylvia S. Mader Concepts of Biology © Zanichelli editore, 2012