Fungi Questions for Plant Biology Exam 1

Questions and Answers

Distinguish between septate and coenocytic hyphae.

Septate hyphae are divided into individual sections that keep organelles in each section but allow cytoplasm to flow freely through the hypha. Coenocytic hyphae are one continuous mass of hyphae and organelles that has no separation.

Distinguish between monokaryotic & dikaryotic, and homokaryotic and heterokaryotic fungi.

Monokaryotic fungi have one nucleus per hypha compartment. Dikaryotic fungi have two nuclei per hypha compartment, each from a different parent. Homokaryotic fungi have nuclei with the same genetic makeup in their mycelium. Heterokaryotic fungi have two or more different types of nuclei within a mycelium.

What is distinctive about centrioles and fungi?

All fungi lack centrioles (except Chytrids); the spindle is inside the nuclear membrane.

Distinguish between yeast form and hyphal form.

The yeast form of fungi grows by budding while the hyphal form grows at the tip. Signup and view all the answers

What is similar between how yeasts and hyphae grow? What is different?

Yeasts grow by budding, while hyphae growth occurs at the tip. Signup and view all the answers

List the features of Phylum Chytridiomycota.

<ol> <li>Aquatic; 2. Decomposers and parasites; 3. Unicellular or hyphal; 4. Have flagella; 5. Sporic meiosis; 6. Chytridion that releases asexual motile zoospores.</li> </ol> Signup and view all the answers

List the features of Phylum Zygomycota.

<ol> <li>Terrestrial; 2. Always coenocytic hyphae; 3. No flagella; 4. Zygotic meiosis; 5. Asexual spores formed inside sporangium; 6. Sexual reproduction by conjugation.</li> </ol> Signup and view all the answers

List the features of Phylum Basidiomycota.

<ol> <li>Terrestrial; 2. Decomposers and parasites; 3. Septate hyphae; 4. Usually not asexual, uses conidia; 5. Sexual spores borne on a basidium; 6. Zygotic meiosis.</li> </ol> Signup and view all the answers

What are the three types of ascocarps?

Apothecium, Perithecium, Cleistothecium. Signup and view all the answers

List the features of Phylum Ascomycota.

<ol> <li>Terrestrial; 2. Septate hyphae or yeast form; 3. Asexual reproduction, spores; 4. Sexual reproduction through asci; 5. Zygotic meiosis.</li> </ol> Signup and view all the answers

Distinguish between a sporangium and a sporangiophore.

The sporangium is a structure where spores are produced. The sporangiophore is a specialized branch that supports the sporangium. Signup and view all the answers

Describe the range of fungal symbioses.

Mycorrhizal, commensal, mutualistic symbioses. Signup and view all the answers

Distinguish between obligate and facultative relationships.

Obligate relationships are essential for survival; facultative relationships allow the fungus to survive without the host. Signup and view all the answers

Distinguish between arbuscular mycorrhizae and ectomycorrhizae.

Arbuscular mycorrhizae interact intracellularly in the plant root, while ectomycorrhizae grow around the root. Signup and view all the answers

Explain why fungal infections in humans or other animals are harder to treat than bacterial or viral infections.

Fungi are eukaryotic organisms, making it harder to target them without harming the host. Signup and view all the answers

Distinguish between crustose, foliose, and fruticose lichen forms.

Crustose: thin and crustlike; Foliose: leaflike; Fruticose: branched form. Signup and view all the answers

Which of the fungi are flagellated, aquatic organisms?

Only the Phylum Chytridiomycota is flagellated and aquatic. Signup and view all the answers

Study Notes

Distinction of Hyphae Types

Septate Hyphae: Divided into individual sections, allowing for organelle localization and cytoplasmic flow.
Coenocytic Hyphae: Continuous mass without separations, containing multiple nuclei and organelles.

Fungal Nucleus Types

Monokaryotic: Fungi with one nucleus per hyphal compartment.
Dikaryotic: Fungi with two nuclei from different parents in each compartment.
Homokaryotic: Fungi with genetically identical nuclei in mycelium.
Heterokaryotic: Fungi with two or more genetically different nuclei in mycelium.

Centrioles in Fungi

All fungi, except Chytrids, lack centrioles; the spindle apparatus forms within the nuclear membrane.

Growth Forms of Fungi

Yeast Form: Grows by budding, involving asexual reproduction.
Hyphal Form: Grows at the tips, utilizing tip extension for growth.

Phylum Chytridiomycota Characteristics

Exclusively aquatic fungi group.
Nutritional roles as decomposers and parasites.
Unicellular or hyphal, with coenocytic hyphae that grow at tips.
Flagellated cells: one posterior flagellum for motility.
Reproduce asexually through motile zoospores.

Phylum Zygomycota Characteristics

Fungi are terrestrial and coenocytic.
Reproduction by zygotic meiosis, no flagella present.
Asexual spores formed in sporangia and released by wind.
Sexual reproduction through conjugation forming zygosporangia.

Phylum Basidiomycota Characteristics

Terrestrial, including decomposers and plant parasites.
Forms positive symbiotic relationships with plants.
Composed of septate hyphae, primarily reproducing sexually via basidiospores.
Forms lichens in obligate and facultative symbiotic relationships.

Types of Ascocarps

Apothecium: Cup or saucer-shaped, large ascocarps.
Perithecium: Flask-shaped with a pore, smaller size.
Cleistothecium: Spherical and poreless, smallest type.

Phylum Ascomycota Characteristics

Terrestrial fungi with either septate hyphae or yeast forms.
No flagella; reproduction occurs asexually or via asci in ascocarps.
Sexual reproduction involves karyogamy and meiosis resulting in eight ascospores.

Sporangium vs. Sporangiophore

Sporangium: Structure for spore production.
Sporangiophore: Specialized supportive branch for sporangium.

Fungal Symbiotic Relationships

Mycorrhizal: Fungi and plant roots partnership enhancing nutrient exchange.
Commensal: One organism benefits, the other remains unaffected.
Mutualistic: Both organisms benefit from the relationship.

Obligate vs. Facultative Relationships

Obligate Relationships: Essential for survival of one or both partners.
Facultative Relationships: Partners can survive independently.

Arbuscular vs. Ectomycorrhizae

Arbuscular Mycorrhizae: Infiltrate plant root cells for nutrient exchange.
Ectomycorrhizae: Surround plant root without entering cells.

Challenges of Fungal Infections

Fungal infections are harder to treat due to eukaryotic nature; treatments targeting prokaryotic organisms typically harm both the fungus and the host.

Lichen Forms

Crustose: Thin, crust-like, adheres tightly to surfaces.
Foliose: Leaf-like, easily removable from substrate.
Fruticose: Branched structures resembling small bushes.

Flagellated Aquatic Fungi

Only Phylum Chytridiomycota consists of flagellated, aquatic organisms.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Prepare for your Plant Biology Exam 1 with this quiz focusing on crucial fungal concepts. Understand the distinctions between various types of hyphae and karyotic forms, essential for mastering mycology. Test your knowledge and boost your confidence before the exam.