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(a) Lichens

Lichens are a symbiotic association between a fungus (usually an ascomycete) and a photosynthetic partner, such as algae or cyanobacteria. The fungus provides protection, water, and nutrients, while the photosynthetic partner supplies organic compounds through photosynthesis. Lichens are ecological pioneers, capable of growing in harsh environments, and they play a role in soil formation and air quality monitoring, as they are sensitive to pollution.

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(b) Mycorrhiza

Mycorrhiza refers to the mutualistic association between certain fungi and plant roots. The fungi enhance the plant’s ability to absorb water and essential nutrients like phosphorus, while the plant provides carbohydrates to the fungi. Mycorrhizae are crucial for plant growth, especially in nutrient-poor soils, and are widely used in sustainable agriculture to reduce dependency on chemical fertilizers.

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(c) Microbes

Microbes are microscopic organisms, including bacteria, fungi, protozoa, and viruses. They play diverse roles in ecosystems and human life. Beneficial microbes contribute to processes like nitrogen fixation, decomposition, and fermentation, while harmful microbes act as pathogens causing diseases. Microbes are also extensively used in biotechnology, medicine, and food production, making them both indispensable and challenging to manage.

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(d) Pathogens

Pathogens are disease-causing microorganisms, including bacteria, fungi, viruses, and protozoa. They infect plants, animals, and humans, disrupting normal biological functions. Examples include Plasmodium (causes malaria), Mycobacterium tuberculosis (causes tuberculosis), and Phytophthora infestans (causes late blight in potatoes). Pathogens are significant in agriculture and public health, necessitating measures for their control, such as antibiotics, vaccines, and pest-resistant crops.

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(e) Rhizopus

Rhizopus is a genus of fungi commonly found in soil, decaying organic matter, and stored food. It is known for its role in food spoilage and diseases like zygomycosis in humans. However, species like Rhizopus oryzae are also used in industrial processes to produce alcohol, organic acids, and enzymes. Rhizopus reproduces both sexually and asexually and is recognized by its characteristic black sporangia, which release spores.

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