Unit 3-2 Flashcards
(14 cards)
What are fungi?
Fungi are eukaryotic organisms, mostly multicellular, that are heterotrophic and absorb nutrients from organic matter. They include yeasts, molds, and mushrooms.
How do fungi obtain nutrients?
Fungi are heterotrophic and acquire nutrients through absorption. They secrete digestive enzymes into their environment and absorb the resulting small molecules.
What are the main characteristics of fungi?
Main characteristics of fungi include:
- Cell walls made of chitin,
- Non-motile,
- Multicellular (except yeasts),
- Reproduce via spores.
How are fungi classified?
Fungi are classified into several groups based on their reproductive structures:
- Chytridiomycota (chytrids),
- Zygomycota (zygote fungi),
- Ascomycota (sac fungi),
- Basidiomycota (club fungi).
What is mycelium?
Mycelium is the vegetative part of a fungus, consisting of a network of filaments (hyphae) that spread out to absorb nutrients.
What is the role of hyphae?
Hyphae are thread-like structures that make up the mycelium. They grow and spread to absorb nutrients, and they also play a role in the reproductive process by producing spores.
What are the types of fungal reproduction?
Fungi reproduce both asexually and sexually:
- Asexual reproduction occurs through the production of spores (conidia, sporangia).
- Sexual reproduction involves the fusion of specialized sexual structures, resulting in the formation of new spores (e.g., basidiospores, ascospores).
What are mycorrhizae?
Mycorrhizae are mutualistic associations between fungi and plant roots. The fungus aids in nutrient absorption (especially phosphorus), while the plant provides carbohydrates to the fungus.
What are lichens?
Lichens are symbiotic organisms made up of a fungus and a photosynthetic partner (alga or cyanobacterium). They are important pioneers in ecosystems like bare rocks and trees.
How do fungi contribute to ecosystems?
Fungi play a key role as decomposers, breaking down dead organic matter and recycling nutrients in ecosystems. They also form symbiotic relationships with plants, animals, and other organisms.
How are fungi beneficial to humans?
Fungi provide food (e.g., mushrooms), are used in the production of antibiotics (e.g., penicillin), and are important in industry for fermentation (e.g., yeast in baking and brewing).
What are some diseases caused by fungi?
Fungal diseases in humans and other animals include:
- Athlete’s foot (caused by Trichophyton),
- Candidiasis (caused by Candida),
- Histoplasmosis (caused by Histoplasma).
What is the role of fungi in plant disease?
Fungi are responsible for many plant diseases, including:
- Rusts, smuts, and blights,
- Powdery mildew and downy mildew.
How did fungi evolve?
Fungi likely evolved from aquatic, single-celled ancestors that shared a common origin with animals. Over time, they adapted to terrestrial environments and diversified into the many forms we see today.
