Unit3-4 Flashcards
(18 cards)
What is the common ancestor of fungi and animals?
Fungi share a unicellular, eukaryotic common ancestor with animals, diverging approximately 1.3 billion years ago in the supergroup Opisthokonta.
How many monophyletic phyla make up the Kingdom Fungi?
Six monophyletic phyla make up the Kingdom Fungi: Blastocladiomycota, Neocallimastigomycota, Chytridiomycota, Glomeromycotina, Basidiomycota, and Ascomycota.
What is the phylum Zygomycota, and how is it classified now?
Zygomycota was traditionally considered a phylum, but it is not monophyletic. It is now reclassified, and members are referred to as ‘traditional zygomycetes.’
What are the two main forms of fungal growth?
Fungi grow as unicellular forms (yeasts) or multicellular forms as mycelia, which are aggregations of hyphae.
What is mycelium in fungi?
Mycelium is the mass of connected hyphae that grows through and digests the substrate. It has a high surface-area-to-volume ratio for efficient nutrient absorption.
What is the primary ecological role of fungi?
Fungi are key decomposers, breaking down cellulose and lignin from wood, releasing carbon, nitrogen, and phosphorus, and making these materials available to other organisms.
How do fungi reproduce sexually?
In sexual reproduction, fungi fuse two haploid hyphae of compatible mating types. Some fungi form a dikaryotic stage (n + n) before forming a diploid nucleus.
What are the main types of fungal reproductive structures?
The four general types of fungal reproductive structures are motile zoospores, zygosporangia, basidia, and asci.
What is a dikaryotic cell in fungi?
A dikaryotic cell contains two haploid nuclei (n + n) that exist independently, unlike diploid cells.
What are mycorrhizae, and what are their functions?
Mycorrhizae are fungal associations with plant roots. They increase nutrient absorption for plants and provide sugars to fungi in return.
What is the difference between arbuscular mycorrhizae and ectomycorrhizae?
Arbuscular mycorrhizae (AM) penetrate root cells and are formed by Glomeromycotina fungi. Ectomycorrhizae surround root cells and are often associated with forest trees, formed by Basidiomycota fungi.
What is a lichen, and what are its components?
Lichens are symbiotic associations between fungi and photosynthetic partners, such as cyanobacteria or green algae. The fungus provides moisture and nutrients, while the photosynthetic partner provides carbohydrates.
What are some examples of fungal diseases in humans?
Candida albicans causes yeast infections, while mycotoxins like aflatoxins can be fatal to humans and are a major food safety concern.
What is chytridiomycosis, and how does it affect amphibians?
Chytridiomycosis is a fungal disease caused by the chytrid Batrachochytrium dendrobatidis, which affects amphibians, causing death due to heart failure as a result of water regulation problems in the skin.
What are glomeromycota fungi known for?
Glomeromycota fungi are obligate symbionts with plant roots and form arbuscular mycorrhizae. They were likely important in the early colonization of land by plants.
What is the significance of the 1000 Fungal Genomes Project?
The 1000 Fungal Genomes Project aims to sequence the genomes of diverse fungal species, contributing to the understanding of fungal biology and evolution.
What is the life cycle of basidiomycetes?
Basidiomycetes, or club fungi, produce basidiospores on club-shaped basidia. They undergo sexual reproduction, and some produce large fruiting bodies like mushrooms.
What distinguishes ascomycetes from other fungi?
Ascomycetes, or sac fungi, form ascospores inside a sac-like structure called an ascus. They include yeasts, molds, and important pathogens like the fungi that cause chestnut blight.
