Kingdom Fungi Chapter 21, page 527

http://www.youtube.com/watch?v=4NO299do_l4

Homework Page 529: Question 1, 2, 3, 4, and 5

Kingdom Fungi (over 100 000 species) Characteristics of fungi: Eukaryotic Multicellular (except for yeast) Heterotrophic : a. lack chlorophyll b. digest food outside the by secreting digestive enzymes into the surrounding area, breaking food molecules into smaller molecules which can be absorbed. They do this in one of 3 ways.

How Fungi Obtain Food i. Saprophyte: - Fungus uses dead or dying organisms for its food source thereby recycling matter into its original elements.

How Fungi Obtain Food ii. Parasite: absorbs food from a live host’s cell ex. Yeast infection Athlete’s foot Ringworm

ringworm

How Fungi Obtain Food iii. Symbiotic relationships in which two or more living organisms benefit. Ex. Lichen which is actually a fungus and a photosynthetic organism (plant or bacteria).

The fungus gives an ability to retain moisture and protection from the elements. The photosynthetic organism gives food.

Kingdom Fungi continued Fungi are made up of thin filaments called hyphae. Each hypha is only one cell thick.

Structure and Function of Fungi In some fungi, cross walls divide hyphae into cells with 1 or 2 nuclei. In the cross walls, there are openings through which the cytoplasm and nuclei can move. Most fungi are made up of filaments called hyphae. In some fungi, the hyphae are divided by cross walls. Copyright Pearson Prentice Hall

Structure and Function of Fungi Some hyphae don’t have cross walls and contain many nuclei. Most fungi are made up of filaments called hyphae. In some fungi, the hyphae lack cross walls and contain many nuclei. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Fungus Structure  The bodies of multicellular fungi are composed of many hyphae tangled together into a thick mass called a mycelium. The mycelium allows a large surface area to come in contact with the food source. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Structure of a Typical Fungus Fruiting body Hyphae The body of a mushroom is part of a mycelium formed from many tangled hyphae. The major portion of the mycelium grows below ground. The visible portion of the mycelium is the reproductive structure, or fruiting body, of the mushroom. Mycelium Copyright Pearson Prentice Hall

A fruiting body is a reproductive structure growing from the mycelium in the soil beneath it.

Kingdom Fungi continued 5. Cell walls of Fungi are made of chitin, a complex carbohydrate. (Same substance in lobster shells.) 6. Most fungi reproduce sexually and asexually.

Asexual Reproduction Asexual reproduction takes place when i. cells divide (binary fission) ii. cells or hyphae break off from a fungus and begin to grow on their own (fragmentation). Ex. Athlete’s foot

iii. a part of the cell pinches off to form new cells (budding) Ex iii. a part of the cell pinches off to form new cells (budding) Ex. yeast iv. spores are produced and then scatter and grow. Ex. most fungi

Conidia and conidiophore

Sexual reproduction involves 2 different mating types, “+” or “-”. When hyphae of opposite mating types meet, they start the process of sexual reproduction by fusing, bringing plus and minus nuclei together in the same cell.

After a period of growth, these nuclei form a diploid zygote. The zygote enters meiosis and produces haploid spores. These spores are capable of growing into new organisms.

Fungi are classified by their reproductive structures We will study four phylum. All end in “mycota”. Zygomycota (common mold) Basidiomycota (mushroom) Ascomycota (sac fungi) Deuteromycota (imperfect fungi)

Reproduction crash course fungi http://www.youtube.com/watch?v=qDwgSWDqKoQ&feature=related

Homework Page 529: Question 1, 2, 3, 4, and 5

Phylum Zygomycota (called Zygomycetes) common mold Grows on cheese, bread, meat, fruit Have life cycles that include a zygospore (resting spore that contains zygotes formed during the sexual phase of the mold’s life cycle.)

Generally lack cross walls in their hyphae, except for their reproductive hyphae.

Diagram of the life cycle of zygomycetes (both asexual and sexual).

Mold Time lapse http://www.youtube.com/watch?feature=fvwp&NR=1&v=JsQHWj2RfXg

Life Cycle

Phylum Ascomycota (page 532) Named for the ascus, a reproductive structure that contains spores. Over 30 000 species (largest Phylum of Kingdom Fungi) Includes yeast

Vocabulary: Conidia (singular conidium) spores Conidiophores (hyphae on which the conidia grow at the very tip) Ascus (plural asci) Forms within the fruiting body Within the ascus, two nuclei of different mating types fuse to form a diploid zygote (2N).

Phylum Ascomycota (page 532)

Phylum Basidiomycota (page 534) Include mushrooms, shelf fungi, puffballs, earthstars, and plant rust. Often called club fungi because many of their fruiting bodies look like clubs.

http://www.youtube.com/watch?v=qDwgSWDqKoQ&feature=related

Phylum Basidiomycota The structure that bears the spores is called a basidium (plural basidia). Basidia are found on the gills.

Life cycle of a Basidiomycete

Phylum Deuteromycota (page 536) Scientists don’t know how these fungi reproduce as they have never been able to observe their life cycles. Also called “imperfect fungi” because our understanding of their life cycles is imperfect.

Includes Penicilloum notatum.

Review Page 545: 1 to 5 7 to 10 12, 13, 15, 16, 17, 18, 22, 23 Answer these questions for Thursday.