Viruses p.122. Viruses are very small structures which can make other organisms sick.

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1 Viruses p.122 Viruses are very small structures which can make other organisms sick. Illness is caused when the viruses invade an organisms cells and use that cell s resources to make more viruses. Viruses are composed of DNA or RNA and are surrounded by a protein shelḷ Sometimes this shell is surrounded by an additional layer similar to a cell membrane. 1

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3 Viruses Viruses present a problem for our classification system. Although viruses can be easily subdivided into groups, it is difficult to determine where they fit in with other organisms. 3

4 Question/Research Examine these characteristics of living things. Which do viruses exhibit? Cells Metabolism Needs water Makes organic molecules Reproduces with inheritance Adapts We will consider viruses alive, but not everyone does. Debatable 4

5 Virus Life Cycle The T4 Virus Infects E. coli bacteria 5

6 Review Viruses are composed of DNA or RNA and are surrounded by a protein shelḷ Viruses present a problem for our classification system. Examine these characteristics of living things. Which do viruses exhibit? Cells Metabolism Needs water Makes organic molecules Reproduces with inheritance Adapts 6

7 Comparison of Kingdoms This section will give an overview of the major differences in the 6 kingdoms. The characteristics we will examine in each group are: Prokaryotic/eukaryotic cells Cell walls Body form/number of cells Source of nutrition Nervous system Reproduction Locomotion Examples 7

Kingdom Bacteria p.132 137 Bacteria have prokaryotic cells.

Each bacteria cell is capable of all the functions needed to survive.

8 Kingdom Bacteria p Bacteria have prokaryotic cells. They have cell walls made of peptidoglycan, which is made of amino acids and sugar. Each bacteria cell is capable of all the functions needed to survive. However, some bacteria live in long chains. Bacteria obtain food by absorbing it from the environment (heterotrophs) or through photosynthesis (autotrophs). There is no nervous system. Reproduction is done asexually. 8

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10 Kingdom Bacteria Many bacteria can not move (are sessile) but some have flagella and can swim. E.g. Escherichia coli lives in our large intestine. E.g. Clostridium botulinum causes botulism and is the source of botox. 10

Kingdom Archaea p.138 139 The Archaea have prokaryotic cells.

11 Kingdom Archaea p The Archaea have prokaryotic cells. They have cell walls. In some it is made of a chemic similar to peptidoglycan. Each Archaea cell is capable of all the functions needed to survive. However, some live in colonies. Some Archaea are heterotrophs, obtaining food by absorbing it from the environment. Some are autotrophs, using chemical reactions powered by heat energy. There is no nervous system. Reproduction is done asexually. 11

Kingdom Archaea Many are sessile but some have flagella and can swim. E.g. extreme thermophiles live in very hot habitats, like the mouth of volcanoes.

12 Kingdom Archaea Many are sessile but some have flagella and can swim. E.g. extreme thermophiles live in very hot habitats, like the mouth of volcanoes. E.g. extreme halophiles live in very salty habitats like salt lakes. 12

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14 Archaea/Bacteria Example life cycle E. Coli Similar to simple cell division The cell expands, elongates then divides Binary division: Asexual reproduction by cell division 14

15 Archaea/Bacteria Example life cycle E. Coli Similar to simple cell division The cell expands, elongates then divides Binary division: Asexual reproduction by cell division 15

several kingdoms (6 35). Therefore this kingdom is very diverse.

Some have cell walls, made of cellulose or chitin.

16 Kingdom Protista p This kingdom contains many distinct groups and should be divided into several kingdoms (6 35). Therefore this kingdom is very diverse. However, all protist cells are eukaryotic. Some have cell walls, made of cellulose or chitin. Most are single celled, some are composed of small colonies of several cells. However, some are composed of billions of cells and are very large. 16

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Kingdom Protista Some protists are heterotrophs

Reproduction may be asexual, sexual or both.

18 Kingdom Protista Some protists are heterotrophs (absorbing or ingesting food), some are autotrophs, and some are combinations of both. There is no nervous system. Reproduction may be asexual, sexual or both. Some are sessile, but others move by cilia, flagella, or contracting the cell membrane. 18

19 Kingdom Protista E.g. Giardia lambia causes beaver fever. E.g. Amoeba are blob like cell that lives in water. E.g. All seaweed. 19

20 Protista Example life cycle Plasmodium Pg. 146 in book 1. Mosquito feeds on infected person (plasmodium enters mosquito) 2. Inside mosquito: plasmodium gametocytes form a zygote () (cell formed after male and female sex cells combine) 3. Zygote divides and breaks open, releasing sporozoites 4. Sporozoites go to mosquitos saliva 5. Mosquito bites human, sporozoites enter human 6. Sporozoites go to liver and reproduce asexually forming new spore like cells 7. these spores enter blood cells and make more spores 8. blood cells rupture releasing mores spores to infect more blood cells cycle continues---> see 1 Key: Gametocytes: male/female sex cells 20

21 Kingdom Fungi p Fungi are eukaryotic. They have cell walls made of chitin, a carbohydrate (long chain of sugars). Most are composed of many cells, but some only a couple (e.g. yeast have 2). They are absorptive heterotrophs, secreting digestive enzymes onto their food and then absorbing it. There is no nervous system. 21

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23 Kingdom Fungi Reproduction is done with spores. The spores can be produced asexually or sexually. 23

24 Fungi are sessile. Kingdom Fungi E.g. White mushroom, Agaricus bispora, is the most common fungi used in cooking. Yeast, Saccharomyces cerevisiae, is used to make bread and drinkable alcohol. Toad stools, Amanita spp., extremely toxic mushrooms. 24

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B. Parasites. Many fungi are parasites of both animal and plants. In humans some pathogenic fungi include the ones that cause Athletes Foot, ringworm and yeast infections.

26 B. Parasites. Many fungi are parasites of both animal and plants. In humans some pathogenic fungi include the ones that cause Athletes Foot, ringworm and yeast infections. Fungal diseases have played and continue to play significant roles in human food crops: 1. Potato blight (Phytophthora infestans) Irish potato famine 2. Wheat Rust (Puccinia graminias). 3. Dutch Elm disease ( Ceratocystis ulmi) 26

Study Guide B. Answer Key. Protists and Fungi

Study Guide B. Answer Key. Protists and Fungi Protists and Fungi Answer Key SECTION 1. DIVERSITY OF PROTISTS 1. eukaryotes 2. protists may be single-celled, colonial, or multicellular 3. No, the size of protists range from microscopic to very large.