Ch 31 Hw
Part B Karyogamy produces a _____.
diploid zygote
Part B - Fungal morphology and physiology The following statements describe something about the body structures or functions of fungi. Identify those statements that are correct. Select all that apply.
-Some fungi secrete digestive enzymes into the environment and then absorb the digested nutrients. -All fungi are heterotrophs; some species live as decomposers and others as symbionts. -Mycelia are made up of small-diameter hyphae that form an interwoven mass, providing more surface area for nutrient absorption. -Some fungi can grow as either filamentous or single-celled forms.
Part E The process indicated by the letter _____ produces a diploid structure.
C
Part F Cup fungi are in the phylum _____.
Ascomycota
Part C Plasmogamy is indicated by the letter _____.
B
Part D Where does meiosis occur in a mushroom?
Basidia
Part C - Ecological interactions of fungi Most fungi are decomposers; they recycle the nutrients from nonliving organic matter. Other fungi are specialized to live in symbiotic relationships with other organisms. Some fungi live as parasites and others as mutualists. Most plants, in fact, could not survive and grow without their fungal partner. This table lists some examples of different fungal strategies for obtaining nutrients. Sort the following fungi based on whether they are decomposers, mutualists, or parasites. Drag each item to the appropriate bin.
Decomposer: -fungi in asso. with a fallen log -fungi in asso. with a dead rabbit -coprophilous fungi Mutualist: -mycorrhizal fungi on pine tree roots -fungi in the family Lepiotaceae Parasite: -Trichophyton spp. -Cryphonectria parasitica -Cordyceps spp. -Septobasidium spp. and an individual scale insect infeted by fungal hyphae
Part C True or false? In most fungi, fertilization is complete after the cells fuse together.
False
Part A Which of the following is a difference between plants and fungi?
Fungi are heterotrophic, and plants are autotrophic.
Part A Almost all of the members of this phylum form arbuscular mycorrhizae in a mutualistic partnership with plants.
Glomeromycota
Part F Which of the following events occurs first in the development of a spore into a mature mushroom?
Hyphae are produced by mitosis.
Part B Which structure is not directly involved in the reproduction of at least one major group of fungi?
Mycelium
Part E Which structure allows the growing mushroom to nourish itself?
Mycelium
Part A Which term describes the fusion of cytoplasm from two individuals?
Plasmogamy
Part A From the human perspective, which of the following kinds of fungi would be considered the least useful or beneficial?
Rusts
Part A Fungi of the phylum Ascomycota are recognized on the basis of their production of _____ during sexual reproduction.
Saclike structures
Part G True or false? Most of the cells in a mushroom contain haploid nuclei.
True
Part A - Structure of multicellular fungi This diagram shows the structure of a multicellular fungus, with an expanded view of two types of hyphae. Identify the structures and determine which hypha is septate and which is coenocytic. (Note that although this diagram shows the two types of hyphae, a fungus can have either one type or the other, but not both.) Drag the labels to their appropriate locations on the diagram of the fungus and hyphae below.
a. mycelium b. pore c. septum d. septate hypha e. coenocytic hypha
Part A Fungi obtain nutrients through _____.
absorption
Part A The diploid phase of the life cycle is shortest in which of the following?
fungus
Part A Fungi produce _____ spores.
haploid
Part A An important example of interaction between fungi and certain other organisms is mycorrhizae, in which the fungal partners _____.
help plants take up nutrients and water
Part A What sexual processes in fungi generate genetic variation?
karyogamy and meiosis
Part D Which of these contains two haploid nuclei?
the heterokaryotic stage of the fungal life cycle