Virus, Bacteria protista fungi (prokaryotes, eukaryotes)

Origin of Cells No one knows for sure, thought to be ____________ No one knows for sure, thought to be ____________ Earth formed: 4.5 billion years Earth formed: 4.5 billion years life origin: 2.5 b.y. life origin: 2.5 b.y.

Viruses Are they living organisms???? No ______________________________--

Viruses and Diseases 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!!!! Antibiotics - No effect! –Quick replication –High mutation rate

Prokaryotes most abundant, single cells most abundant, single cells organized organized  _________________  plasma membrane  cell wall Types: Types: 1. ______________ 2. archaea

1. Bacteria Additional features : Additional features : –Flagella, long strands used in ____________ –Pili, short strands used as docking cables

Bacteria reproduce: ___________________ Bacteria reproduce: ___________________ bacteria exchange genetic information: conjugation bacteria exchange genetic information: conjugation

three shapes: three shapes: –Coccus: _______ –Bacillus: ______ –Spirillum: ____

1. E. COLI 0157:H7 outbreaks in US, per year: outbreaks in US, per year: –73,000 infections/61 deaths infections from: 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 Symptoms: bloody diarrhea, kidney failure Prevention: _________________________- Prevention: _________________________- Bacteria-Foodborne illness

2. Salmonella outbreaks: outbreaks: –40,000 cases/600 people die infected by: infected by: –contaminated ground beef, pork, eggs, poultry products –improperly pasteurized dairy products Symptoms: bloody diarrhea Symptoms: bloody diarrhea Prevention: good higiene, not to eat raw eggs (even cookie dough), meat well cooked Prevention: good higiene, not to eat raw eggs (even cookie dough), meat well cooked

3. Campylobacter causing diarrhea, cramping, abdominal pain, fever, nausea, vomiting causing diarrhea, cramping, abdominal pain, fever, nausea, vomiting Outbreaks: Outbreaks: –1 million/100 people die infections from: infections from: –raw poultry meat, 80% chickens in US carriers

2. Archaea from prokaryotic ancestors to eukaryotes from prokaryotic ancestors to eukaryotes live _____________________ live _____________________ cell walls different from bacteria with unique lipids and rRNA sequences cell walls different from bacteria with unique lipids and rRNA sequences

Eukaryotes Cells with ______________ Cells with ______________ Types: Types: –Protista, diverse group –multicellular kingdoms:  Fungi  Plants  animals

Are _______________ fungi, plants, or animals Are _______________ fungi, plants, or animals employ almost every form of __________________________ employ almost every form of __________________________ Reproduce: Reproduce: –asexually most of the time: fission and budding –sexually only in times of stress Some survive harsh environmental conditions by forming cysts, a dormant form of cell Some survive harsh environmental conditions by forming cysts, a dormant form of cell movement accomplished by diverse mechanisms: movement accomplished by diverse mechanisms:  Cilia  Flagella  Pseudopods  gliding mechanisms Protista

Types: Types:  single cell: paramecium, amoeba  Aggregation, transient collection of cells: slime molds  Colonial multicellular: permanent cells in contact: algae

Fungi Similar to plants but _______chlorophyll: heterotrophs Similar to plants but _______chlorophyll: heterotrophs differ from plants in: differ from plants in: 1.have filamentous bodies called ________ 2.have cell walls made of chitin

Reproduce: Reproduce: 1.asexually 2.Sexually reproductive structures: reproductive structures:  gametangia produce ______________-  sporangia produce haploid spores that can be dispersed

Heterotrophs: _______________________________________ ______________ Heterotrophs: _______________________________________ ______________ Fungi and bacteria: principal decomposers Fungi and bacteria: principal decomposers mutualistic associations ecologically important: 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 years 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

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 _______