KINGDOM FUNGI

GENERAL CHARACTERISTICS All fungi are eukaryotes (nucleus and other

organelles).

Most fungi are multicellular, but some, like yeasts, are unicellular.

Fungi are heterotrophic, but they cannot ingest their food because their cell walls are too thick.

GENERAL CHARACTERISTICS Fungi absorb nutrients into their cells by

releasing enzymes that break down nutrients before they are taken in.

Fungi have cell walls (like plants) but do not contain chloroplasts.

HETEROTROPHIC FUNGI Saprophytes

Live off dead/dying plants and/or animals. i.e. mushrooms

Parasites Live directly off a host. i.e. athlete’s foot

Symbionts Live in a close relationship with other organisms. i.e. lichen

KINGDOM FUNGI We will be studying 5 phyla in kingdom fungi:

Oomycota (p. 409) Zygomycota (p. 410) Ascomycota (p. 411) Basidiomycota (p. 414) Deuteromycota (p. 415)

Mycota = mykos (Greek for mushroom)

STRUCTURE OF A TYPICAL FUNGUS The body of a typical fungus is composed of

masses of tangled filaments called hyphae (singular = hypha).

STRUCTURE OF A TYPICAL FUNGUS The entire mass of tangled filaments if

collectively called the mycelium.

The mycelium increases that surface area so that more fungus can come into contact with the food (like bread).

CROSS WALLS One way to tell one fungus from another is

by the presence or absence of cross walls.

Each cell may have 1 or more nuclei. The cross walls are made of cellulose or

chitin. Both of these are carbohydrates.

REPRODUCTION OF FUNGI Most fungi can either reproduce asexually (1

parent) or sexually through the use of mating types + and -.

LIFE CYCLE OF THE BLACK BREAD MOLD Label the diagram:

A: spores B: sporangium C: sporangiophore D: sporangium E: spores F: stolons G: zygosporangium H: zygospore I: rhizoids J: gametangia

LIFE CYCLE OF THE BLACK BREAD MOLD Asexual reproduction:

Step 1: Sporangia produce (N) spores (up to 40,000 per sporangium!)

Step 2: Sporangia open when mature and release (N) spores to wind, water and gravity.

Step 3: Spores germinate when temperature and moisture allow them to.

Step 4: New masses of hyphae form which grow into mycelia.

LIFE CYCLE OF THE BLACK BREAD MOLD Sexual reproduction:

Step 1: Mating types + and – fuse together.

Step 2: Gametangia are formed which produce (N) gametes.

Step 3: Gametes fuse together to form a (2N) zygosporangium. A thick wall forms around it to produce a (2N) zygospore.

LIFE CYCLE OF THE BLACK BREAD MOLD Sexual reproduction:

Step 4: The zygospore may remain dormant. Later it undergoes meiosis and grows a hypha.

Step 5: Hypha grows a sporangium which produces (N) spores.

Step 6: Spores can germinate and grow hyphae/ mycelia.

** Alternation of generations. The 2N portion of the life cycle if only during the zygospore period. **

LIFE CYCLE OF THE BLACK BREAD MOLD