1. Kingdom Fungi
Finding the Fungus Among Us

2. Characteristics of Fungi
Eukaryotic
Most are Multicellular
Filamentous body plan
Heterotrophic by Absorption
Produce spores by sexual and asexual reproduction
Haploid for part or most of life cycle
Cell wall made of chitin
No movement: change location by growth of body or dispersion of spores

3. The Filamentous Body of a Fungus
(c) Hyphal Cells (cutaway)
(a) Mycelium
Haploid Nuclei
Cytoplasm
(a) A fungal mycelium spreads over decaying vegetation. The mycelium is composed of (b) a tangle of microscopic hyphae, only one cell thick, (c) portrayed in cross section to show their internal organization.
Septum
(b) Individual Hyphae
Pore
Cell Walls

4. Body Plan of Fungi Mycelium = network of filaments
Hypha = individual filament (plural = hyphae)
Septum = partition dividing cells, has pore for distribution of nutrients
Reproductive structure extends from main body, produces spores

5. Fungal Nutrition Heterotropic by absorption Three nutritional modes
secrete digestive enzymes
digest macromolecules outside the body
absorb digested nutrients
Three nutritional modes
Saprophytic = digestion of dead organisms
Parasitic = digestion of live organisms, causing disease
Mutualistic = beneficial relationship for two independent organisms

6. Saprophytes
Fungus on pinecone, Soil fungus between soy seedlings, woodrot

7. Parasites
Clockwise from top right: Athlete’s foot fungus, affected feet, candida, ringworm, ergot, corn smut

8. Lichen: Mutualism Between Alga and Fungus
Algal Layer
Fungal Hyphae
Attachment Structure

9. Mycorrhizae: Mutualism Between Fungus and Plant Roots

10. Applying Your Knowledge
Parasitic
Saprophtyic
Mutualistic
Which mode of nutrition
Provides a benefit for the fungus and its symbiotic partner?
Is shown by athlete’s foot fungus?
Involves digestion of dead organisms?

11. Sexual Reproduction Hypha from mycelia of opposite mating types fuse
Fusion of two haploid nuclei forms diploid zygote
Zygote produces haploid spores by meiosis
Each spore germinates to produce a haploid mycelium

12. Forming Female Gametes
Chythrid Fungi
Flagellated, swimming spores require water for dispersal
Ancestral group, gave rise to modern fungi
Forming Male Gametes
Forming Female Gametes

13. Zygote Fungi Live in soil and on decaying plant matter
Zygosporangia = reproductive structures producing haploid spores

14. Sac Fungi
Ascus = sac that surrounds haploid ascospores

15. Club Fungi
Basidium = club-shaped reproductive structure that produces basidiospores

16. Fusion forms diploid zygote. Mushroom gills bear reproductive basidia.
Club Fungus Life Cycle
Haploid Nuclei
Fusion forms diploid zygote.
Basidia on gills
The mushroom (top left) is a reproductive structure formed from aggregated hyphae made up of cells that each contain two haploid nuclei. Within the cap, leaflike gills bear numerous basidia (top right). Within each basidium, the two haploid nuclei fuse, producing a diploid zygote. The zygote then undergoes meiosis, forming haploid basidiospores that are released from the basidia (right). After dispersal by wind or water, the basidiospores germinate, forming haploid hyphae. When hyphae of different mating types meet, some of the cells fuse. These cells, each containing two haploid nuclei, produce an extensive underground mycelium (bottom). Under appropriate conditions, portions of the mycelium aggregate, swell, and differentiate, poking up through the soil as mushrooms and completing the cycle.
MEIOSIS
Basidiospores (haploid)
Haploid 1n
Mushroom gills bear reproductive basidia.
Diploid 2n

17. - Club Fungus Life Cycle + Basidiospores (haploid) Basidia on gills
Hyphae aggregate to form mushroom
The mushroom (top left) is a reproductive structure formed from aggregated hyphae made up of cells that each contain two haploid nuclei. Within the cap, leaflike gills bear numerous basidia (top right). Within each basidium, the two haploid nuclei fuse, producing a diploid zygote. The zygote then undergoes meiosis, forming haploid basidiospores that are released from the basidia (right). After dispersal by wind or water, the basidiospores germinate, forming haploid hyphae. When hyphae of different mating types meet, some of the cells fuse. These cells, each containing two haploid nuclei, produce an extensive underground mycelium (bottom). Under appropriate conditions, portions of the mycelium aggregate, swell, and differentiate, poking up through the soil as mushrooms and completing the cycle.
“+” Mating Strain
“-” Mating Strain
Basidiospores germinate forming hyphae (haploid). + -
Haploid 1n
Hyphae fuse, but haploid nuclei remain separate in binucleate cells
Diploid 2n

18. Imperfect Fungi Sexual reproduction has not been observed
Counterclockwise from top left: Staurospore, Penicillium on apple (Coremia), Sphaeropsis

19. Applying Your Knowledge
Chytrids
Zygote Fungi
Sac Fungi
Club Fungi
Imperfect Fungi
Which group of fungi
Encloses haploid spores within an ascus?
Has flagellated gametes?
Has an umbrella-shaped reproductive structure called a basidium?
Has not shown sexual reproduction?

20. Applying Your Knowledge
Chytrids
Zygote Fungi
Sac Fungi
Club Fungi
Imperfect Fungi
Which group of fungi
Are found on as a topping your mushroom pizza?
Caused the pizza dough to rise?
Make up the fuzzy structure on the two-week old loaf of bread in your cupboard?

21. Applying Your Knowledge
Prokaryotes
Protists
Fungi
Plantae
Animalia
Which kingdom/domain
Has organisms that are heterotrophic by ingestion?
Has cell walls made of chitin?
Reproduces by binary fission?