chapter 8: Protists and Fungus Section 2: Fungus(part 1)

PROTIST AND FUNGUS

Section 2: Fungi

• What is fungi
• Structure of fungi
• Other characteristics of fungi
• Reproduction

What are Fungi? 

Do you think you can find any fungi in your house or apartment? You have fungi in your home if you have mushroom soup or fresh mushrooms. What about that package of yeast in the cupboard?  Yeasts are a type of fungus used to make some breads and cheeses. You alsomight find fungus growing on loaf of bread or an orange, or mildew fungus growing on yourshower curtain.

Origin of Fungi

• Although fossils of fungi exist, most are not useful in determining how fungi are related to other organisms.
• Most species of fungi are many-celled.
• The body of a fungus is usually a mass of many-celled, threadlike tubes called hyphae (HI fee)
• The hyphae produce enzymes that help break down food outside of the fungus.
• Then, The fungal cells absorb the digested food.
• most fungi are known as saprophytes. Saprophytes are organisms that obtain food by absorbing dead or decaying tissues of other organisms.
• Others are parasites. So, they can obtain their food directly from living things.
  

  Other Characteristics of Fungi

  similarities with plants	Differences with plants
  Grow anchored in soil	No specialized tissues  and organs of plants,  such as leaves and roots
  Have a cell wall	Not contain chlorophyll  and cannot undergo photosynthesis

• Fungi grow best in warm , humid areas.
  
  
  Examples: Tropical forest, between toes..

Reproduction

• Asexual and sexual reproduction in fungi usually involves the production of spores.
• A spore is a waterproof reproductive cell that can grow into a new organism.
• In a sexual reproduction, cell division produces spores. These spores will grow into new fungi that are genetically identical to the fungus from which the spores came.
• Fungi are not identified as either male or female. Sexual reproduction can occur when the hyphae of two genetically different fungi of the same species  grow close together. 
• If the hyphae join, a reproductive structure will grow.
• Following meiosis- spores are produced that will grow into fungi.
• These fungi are genetically different fromeither of the two fungi whose hyphae  joined during sexual reproduction. Based on the type of structure formed by the joining of hypae.

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First part ends.