MCQ’s
Notes with Exercise
Class 11th Biology Chapter 8, Fungi, covers the characteristics, classification, and importance of fungi in nature. Here’s a general overview:
- Characteristics of Fungi:
- Eukaryotic Organisms: Fungi are eukaryotes, meaning they have membrane-bound organelles and a nucleus.
- Heterotrophic: Fungi do not photosynthesize. They obtain nutrients by absorbing organic matter from their surroundings.
- Cell Wall: Their cell walls are made of chitin, unlike plants, which have cell walls made of cellulose.
- Unicellular and Multicellular Forms: Fungi include both unicellular organisms like yeast and multicellular organisms like mushrooms.
- Structure of Fungi:
- Hyphae: The basic structural unit of fungi. Hyphae are thread-like filaments that collectively form a network called a mycelium.
- Spores: Fungi reproduce via spores, which can be spread by wind, water, or animals.
- Reproduction: Fungi reproduce both asexually (through budding or spores) and sexually (via fusion of hyphae from two individuals).
- Classification of Fungi:
- Zygomycota: These fungi produce spores in a structure called zygospore. Example: bread mold (Rhizopus).
- Ascomycota: Also known as sac fungi, they produce spores in sac-like structures called asci. Example: yeast, morels.
- Basidiomycota: Known as club fungi, they produce spores on club-shaped structures called basidia. Example: mushrooms, puffballs.
- Deuteromycota: Also called imperfect fungi, they do not have a known sexual reproduction stage. Example: Penicillium, which is used to produce antibiotics.
- Role of Fungi in Nature:
- Decomposers: Fungi play a crucial role in ecosystems as decomposers, breaking down dead organic material and recycling nutrients.
- Symbiotic Relationships: Fungi form mutualistic relationships like mycorrhizae with plants, where fungi help plants absorb nutrients from the soil.
- Pathogens: Some fungi are parasitic and cause diseases in plants, animals, and humans (e.g., athlete’s foot, ringworm).
- Economic Importance of Fungi:
- Food Production: Fungi like yeast are used in the production of bread, alcohol, and cheese.
- Medicine: Fungi produce antibiotics such as penicillin and other pharmaceuticals.
- Biotechnology: Fungi are used in research and industrial applications for enzyme production and biodegradation.
This chapter provides insight into the diverse nature of fungi, their ecological roles, and their impact on human life.