Presentation is loading. Please wait.

Presentation is loading. Please wait.

Ferns, fern allies, and fungi. Alternation of generations.

Similar presentations


Presentation on theme: "Ferns, fern allies, and fungi. Alternation of generations."— Presentation transcript:

1 Ferns, fern allies, and fungi

2 Alternation of generations

3 Fungi Basic Structure of Fungi 1.Hyphae, tubular threads 2.Mycelium, a mass of hyphae Mycology 1.Study of fungi 2.Mycologists scientists who study fungi

4 Vocabulary Hyphae – long filaments in the body of a fungus. Mycelium – the fungus body; a collection of interconnecting hyphae. Heterothallic – when a fungus has two mating types (+ and -). Sporangia – fruiting bodies involved in asexual production of spores. Conidiophores – fruiting bodies involved in asexual production of conidia spores. Basidiocarps – fruiting bodies involved in production of sexual spores only in Basidiomycetes. Gametangia – reproductive tissue formed between two hyphae of complementary mating type during sexual reproduction.

5 Phylum Zygomycota 1. Habitat a.Organic matter; untreated breads b.Soil (nematode-trapping fungi), dung-fungi 2.Shape hyphae coenocytic 3.Reproduction—Rhizopus (bread mold) a.Asexual 1)Sporangiophores grow upright and produce sporangia at their tips 2)Numerous spores produced in each sporangium b.Sexual 1)Conjugation of different mating strains 2)Formation of progametangia 3)Gametangia merge, becoming large multinucleate cell 4)Wall develops around cell, forming the zygospore

6

7 1. One group of zygomycetes forms mycorrhizae, which are mutualistic associations with plant roots. 2. They reproduce asexually, through asexual spores contained in sporangia. 3. When reproducing sexually, hyphae of two different mating strains meet, create gametangia, fuse, and subsequently create a diploid zygosporangium and zygospore. 3. The zygospore goes through meiosis and produces haploid sporangia.

8

9 Sac fungus Lab p 143 Use the previous slide to label the lab figure

10 Basidiomycetes (Club Fungi) 1.Habitat a.Saprophytes 1)Mushrooms (toadstools) 2)Puffballs, earth stars, jelly fungi, stinkhorns b.Parasites 1)Shelf or bracket fungi 2)Rusts, smuts 2.Shape a.Mycelium septate with pores b.Uninucleate or binucleate stages of mycelium

11 Mycelium septate with pores

12 a.Asexual infrequent, rare b.Sexual 1)Hyphae of mycelium are monokaryotic 2)Hyphal cells of compatible mating types may unite, initiating a new dikaryotic mycelium 3)Formation of clamp connection, with one nucleus migrating into clamp 4)Mitosis and formation of crosswalls 5)Dikaryotic mycelium may become very dense, forming the button, which may penetrate the surface and expand into the basidiocarp (mushroom) 6)Gill of mushroom has numerous basidia 7)As each basidium matures, the two nuclei unite, and then undergo meiosis; the four nuclei become the nuclei of the four basidiospores

13

14 Start Lichens 26 September 2012

15 Lichens 1.Symbiosis between a fungus and an alga a.Can be viewed as a controlled parasitism of the alga by the fungus b.About 25,000 species of lichens 2.Grow very slowly 3.May live 4,500 years or more and are very tolerant of extreme environmental conditions, except for pollution and nuclear radiation

16 Lichens cont. 4.Forms a spongy body (thallus) a.Consists of three or four layers of cells or hyphae 1)Upper cortex 2)Algal layer 3)Medulla 4)Lower cortex 5)Rhizines b.Growth forms 1)Crustose lichens often brightly colored, crusty patches 2)Foliose lichens leaf-like thalli 3)Fruticose lichens thalli branched and cylindrical in shape Red tips are fruiting bodies

17 Lichens cont. c.Algal partners three genera of green algae and one of blue-green bacterium involved in 90% of lichen species d.Fungal partners almost all lichens have members of the sac fungi as their fungal component e.Classification lichen species identified according to the fungus present

18 Crustose lichen

19 Foliose lichens

20 Fruticose lichens

21 Lichen types

22 Lichens cont. Reproduction 1. Lichens dispersed primarily by asexual means some produce powdery clusters of hyphae and algae called soredia 2. Sexual reproduction similar to the sac fungi, except ascocarps produce spores continually for many years

23 Asexual reproduction

24 Ferns and fern allies

25 A.General Characteristics 1.Xylem and phloem present internal conducting tissues for water and food, respectively 2.Spores, but no seeds 3.Ferns and relatives ("fern allies") B.Classification 1.Phylum Psilotophyta (Whisk Ferns) no leaves or roots 2.Phylum Lycophyta (Club Mosses and Quillworts) small leaves called microphylls 3.Phylum Equisetophyta (Horsetails & Scouring Rushes) ribbed stems and whorled leaves 4.Phylum Polypodiophyta (Ferns) large, complex leaves called megaphylls

26 Mosses Phylum Bryophyta – Some plants are called mosses, but are not Irish moss - dicot Raindear moss- lichen Spanish moss – bromeliad – 3 classes Peat moss True moss Rock moss – Leave,s stems, rhizoids (no roots)

27 Mosses cont. Sexual Reproduction 1. Female gametangium called the archegonium (flask shaped) 2.Male gametangium called the antheridium (club shaped) 3.Gametangia produced at tips of leafy gametophytes 4.Sperm are flagellated and reach archegonium by swimming in a film of water 5.Sporophyte develops in base of archegonium and grows into a foot, seta, and a capsule 6.Calyptra sits on top of capsule 7.Meiosis takes place in the capsule producing spores 8.Peristome teeth at rim of capsule aid in dispersal of spores 9.Spores germinate on moist soil and develop into an algal-like protonema 10.Protonema develops tiny "leafy" buds which will produce the upright gametophytes

28

29 Phylum Equisetophyta A.Structure and Form 1.Equisetum = means "horsetail" a.Branching forms called horsetails b.Unbranched forms called scouring rushes 2.Silica content of stems—"Colonial Brillo" 3.Herbaceous plants less than 4 feet tall 4.Whorls of branches and leaves (microphylls) 5.Stems distinctly ribbed 6.Canal system in stem a.Carinal canal, involved in water conduction b.Vallecular canal is air filled 7.Ancient tree-like forms now extinct

30 Chapter 21 You will be responsible for Equisetophyta and Polypodiophyta in this chapter only

31 Equisetum

32 B.Reproduction 1.Cones or strobili formed 2.Sporangiophores bear the elongated sporangia 3.Spores produced by meiosis in the sporangia 4.Elaters are appendages of the spores, aid in spore dispersal 5.Spores germinate and produce green pincushion-like gametophytes 6.Male and female gametophytes formed; female gametophytes become bisexual after 4-6 weeks

33

34 Sexual cycles

35 See figure in text

36 Phylum Polypodiophyta A.Structure and Form 1.Tiny floating (aquatic) ferns to giant tropical tree ferns 2.Leaves called fronds young coiled fronds called fiddleheads 3.Underground stems called rhizomes 4.Abundant in tropical climates

37 Aquatic fern

38 B.Reproduction 1.Fronds may bear sporangia on underside 2.Sporangia form clusters called sori (sorus: singular) 3.Sporangia may be protected by tissue called indusium 4.Meiosis occurs in sporangia 5.Spores (meiospores) violently ejected from sporangium by action of the annulus

39 Indusium

40 Annulus (ring like structure)

41 Reproduction cont 6.Spores grow into heart-shaped prothallus which is the gametophyte phase, this is what we are growing on the agar plates 7.Archegonia and antheridia produced on prothallus 8. Part or all of the gametophyte prothallus dies, so sporophyll is independent 9.Fertilization results in a zygote (2n) which grows into an embryo 10.Embryo develops into new fern plant (sporophyte)

42 Prothallus

43 Fern life cycle - see figure in lab book

44 Use the lab book and the text book book along with this power point to understand these plants

45 Conifers see figure in lab book

46


Download ppt "Ferns, fern allies, and fungi. Alternation of generations."

Similar presentations


Ads by Google