Virus Bacteria protista fungi prokaryotes eukaryotes Origin of
Virus, Bacteria protista fungi (prokaryotes, eukaryotes)
Origin of Cells No one knows for sure, thought to be ______ n Earth formed: 4. 5 billion years n life origin: 2. 5 b. y. n
Viruses n Are they living organisms? ? n No _______________--
Viruses and Diseases 1. 2. 3. 4. 5. 6. 7. Common cold – attack respiratory tract Measles – skin Rabies – nerve cells Herpes virus – mouth and lips, sexual transmission AIDS – white blood cells Ebola – a hemorrhagic fever Biological Weapons These diseases are difficult to fight!!!! n Antibiotics - No effect! n – Quick replication – High mutation rate
Prokaryotes most abundant, single cells n organized n § _________ § plasma membrane § cell wall n Types: 1. _______ 2. archaea
1. Bacteria n Additional features : – Flagella, long strands used in ______ – Pili, short strands used as docking cables
n Bacteria reproduce: __________ n bacteria exchange genetic information: conjugation
n three shapes: – Coccus: _______ – Bacillus: ______ – Spirillum: ____
Bacteria-Foodborne illness 1. E. COLI 0157: H 7 n outbreaks in US, per year: – 73, 000 infections/61 deaths n infections from: – uncooked ground beef (cattle carry the pathogen in their intestines without getting sick) – contaminated dairy products – Vegetables, unpasteurized juice, petting zoos Symptoms: bloody diarrhea, kidney failure n Prevention: _____________n
2. Salmonella n outbreaks: – 40, 000 cases/600 people die n infected by: – contaminated ground beef, pork, eggs, poultry products – improperly pasteurized dairy products Symptoms: bloody diarrhea n Prevention: good higiene, not to eat raw eggs (even cookie dough), meat well cooked n
3. Campylobacter causing diarrhea, cramping, abdominal pain, fever, nausea, vomiting n Outbreaks: n – 1 million/100 people die n infections from: – raw poultry meat, 80% chickens in US carriers
2. Archaea n n n from prokaryotic ancestors to eukaryotes live ___________ cell walls different from bacteria with unique lipids and r. RNA sequences
Eukaryotes Cells with _______ n Types: n – Protista, diverse group – multicellular kingdoms: § Fungi § Plants § animals
Protista n Are ________ fungi, plants, or animals n employ almost every form of _____________ n Reproduce: n Some survive harsh environmental conditions by forming cysts, a dormant form of cell n movement accomplished by diverse mechanisms: – asexually most of the time: fission and budding – sexually only in times of stress § § Cilia Flagella Pseudopods gliding mechanisms
n Types: § single cell: paramecium, amoeba § Aggregation, transient collection of cells: slime molds § Colonial multicellular: permanent cells in contact: algae
Fungi n Similar to plants but _______chlorophyll: heterotrophs n differ from plants in: 1. have filamentous bodies called ____ 2. have cell walls made of chitin
n Reproduce: 1. asexually 2. Sexually n reproductive structures: § § gametangia produce _______sporangia produce haploid spores that can be dispersed
Heterotrophs: ____________________ n Fungi and bacteria: principal decomposers n n mutualistic associations ecologically important: – Mycorrhizae: fungi-plant § expedite the plant’s absorption of essential nutrients in the roots – Lichens: fungi-algae (cyanobacteria) § can grow in harsh habitats, such as bare rock
Practice questions 1. Bacteria A) are prokaryotic B) have been on the earth for at least 2. 5 billion C) are the most abundant life form on earth D) All answers are correct 2. Viruses are: A) protein coats that contain DNA or RNA B) simple eukaryotic cells C) simple prokaryotic cells D) Alive years
3. The main problem in classifying protists is that: A) all have a common lifestyle B) all are unicellular C) all are photoautotrophic D) any eukaryotic organism that is not plant, animal, or fungi is a protist 4. The main body of a fungus is the ____ 5. Fungi reproduce both _______ 6. Lichens are mutualistic associations between _______
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