Download Bacteria and Viruses Notes Review: Archaebacteria • Are

Bacteria and Viruses Notes
Review: Archaebacteria
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Are __________________________: Unicellular organisms without nuclei with No organelles. Have Cell Walls.
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Archaebacteria is the _______________ organism.
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Lacks peptidoglycan. DNA is more similar to _________________________________, denotes lineage.
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Live in extreme environments: No oxygen (anoxic) such as places like Hot Springs and the Deep ocean
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Make energy by a process called: _______________________________________________________
Review: Eubacteria
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Are _________________________: Unicellular organisms
without nuclei with No organelles. Have Cell Walls.
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Are characterized by… _________________________________,
Chemical nature of ____________________________________,
The way they _________________________________________,
The way they obtain ____________________________________
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Cell Walls thicker (peptidoglycan, a carbohydrate)
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Live anywhere: Freshwater, saltwater, on land, in the human
body
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Can be heterotrophic, photosynthetic and chemosynthetic
Bacterial Feeding
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______________________________________ – take in organic molecules for energy and a supply of Carbon.
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______________________________________ – use chemicals for gaining energy.
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______________________________________ – create their own energy. Photoautotrophs – gain energy from
light from the sun to convert CO2 and water into energy. Chemoautotrophs – make organic carbon from CO2.
Do not require light, but instead use energy from chemical reactions using Ammonia, HS, nitrates, S, and Fe.
Live in the deep ocean.
Note: In bacterial infections, they harm the host by either destroying cells for food or releasing toxins (poisons) in the
host’s body.
Bacterial Reproduction
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_____________________________________________ – asexual reproduction. Chromosomes are replicated
and move to the poles of the cell (Mitosis) Occurs very fast (every 20 mins!)
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As the bacterium gets larger, it pinches in between, creates cells that are Genetically _______________
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____________________________________________ – sexual reproduction. Through a pilus (pili) bacterial cells
exchange genetic information
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Not genetically identical. Creates new genetic compositions (genetic diversity) like Meiosis.
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Allows for greater survival in a changing environment
Bacteria Survival
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Bacteria who need oxygen are called ________________________________________________
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Bacteria who are killed by oxygen are called __________________________________________
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When conditions become harsh, they can form an _____________________________ that contains DNA.
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When conditions improve, the endospore germinates. Can take months! Bacteria can be harmful to people for
these reasons. Bacteria forming on food creates toxins that can harm humans.
Bacteria are important in the supporting roles of life.
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Some are ______________________________________ that give off oxygen.
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Some are _______________________________________ that break down nutrients in dead matter and
the atmosphere.
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Some help in ____________________________________________________ so plants can turn
Nitrogen gas into a useable form.
Human Uses for Bacteria: Food, Beverages, mining, water treatment, medicine, digestion in the human intestines.
What is a Virus?
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Viruses are non-living particles of nucleic acid, protein and some lipids that cause influenza.
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Composed of DNA or RNA in a protein coat called a capsid.
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Viruses that only infect bacteria are called bacteriophages.
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Named after their ________________ or _________________
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Likely evolved later since they are dependent on living things.
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Why Non-Living?
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Cannot ___________________ without infecting a
host cell
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Do not ______________ and ___________________
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Do not _____________________ to the environment.
Note: Like Bacteria, Viruses produce disease by disrupting the body’s
normal equilibrium. They either directly attack cells or cause cells to
change their patterns of growth or influence their function in the body.
Viral Reproduction
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_________________________________________ cycle
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Virus attaches to host cell
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Inserts viral nucleic acid and inserts it into the host cell’s
chromosome (________________________)
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Gets replicated as host cell _________________ (through mitosis)
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Can remain inactive for a long period of time.
_________________________________________ cycle
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Starts as the lysogenic cycle until triggered.
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Takes over cell machinery to make virus only! (Chops up cell’s
DNA to shut down all defenses.)
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Viruses are assembled in the host cell
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Burst out of the host cell releasing new virus
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30 min = 200 viruses
HIV Virus
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________________________________: Use RNA instead of DNA
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Reverse transcriptase creates DNA from the RNA in the host cell
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In Sub-Saharan Africa over 23 million living with HIV/AIDS, 4 million
infected each year.
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HIV contact via Saliva/Sexual Contact, Mucus Membranes, Shared hypodermic needles, Blood transfusion (rare)
Preventing Disease
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____________________________________________ – preparation of weakened or killed pathogens that is
injected for the creation of immunity against the pathogen.
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_______________________________ – Sterilization by Heat, Disinfectants, Food Storage (Cans, etc)
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____________________________________ – Compounds that block the growth and reproduction of bacteria.
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One of the major reasons the for dramatic increase in life expectancy in the past 200 years.
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Not effective against ________________________.