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Sam, Elana, Andrew, Sarah, Aaron and Beth. Mentor- Ms. Krasnick

Microbiology

Microbes are found everywhere, and they are small single-celled organisms. Our bodies are home to trillions of microbes. They are billions of years old because they can adapt to inconstant environments.
What is a microbe?

  • Oldest form of life on earth
  • Some types of microbes existed for billions of years make 3-4 billion years ago
  • Single cell organisms
  • Can’t be seen by the naked eye
  • Can be seen with microscopes
  • 95% of microbes are harmless
  • Some microbes look external image microbes.jpglike pom poms
  • Micobes are in the food you eat, the water you drink and the air you breathe
  • They are everywhere
  • Can multiply in minutes
Types of microbes:
Bacteria

Are found virtually everywhere
  • Can withstand extreme temperatures, acidities and radiation
  • Can cause disease but are also very helpful
  • Prokaryotes. Do not have nuclei
  • Earliest forms of life
  • Some organelles are bacteria
  • Rod, spiral or spherically shaped. Some are singular and some group together
  • Get around by long hair (called flagella) or slime so they can glide
  • Photosynthetic bacteria makes own “food” others absorb it
  • “food” can be unusual (iron, sulfur) Archaea.
external image _wsb_500x363_Bacteria1.jpg
  • Cousin of bacteria and are very similar to them
  • Earliest forms of life
  • Three types: Crenarchaeota, Euryarchaeota, Korarchaeota
  • Crenarchaeota characterized to tolerate exte=remes in temperature and acidity
  • Euryarchaeota methane producers and salt lovers
  • Korarchaeota Everything else
  • Archaea look like bacteria
  • Found almost everywhere
  • Prokaryotes. No nucleus
  • Get around by long hair (called flagella)
Viruses
  • Made of DNA or RNA and a coating of protein
  • Only purpose is to reproduce. Reproduce by attaching to other cells. Once attached they infect and take over the cell and it explodes with a new batch of viruses.
  • Can be 10,000 times smaller than bacteria. Smallest microbe
  • Found anywhere there are cells to infect and have evolved to infect anything
  • Viruses are generally specific to one type of cell and related cells
Fungi
  • Range in size from microscopic to the largest known living organism
  • Largest is a 3.5 mile underground mushroom
  • Eukaryotes. Has nucleus, enclosed is DNA
  • Can look like plants but are not photosynthetic
  • Some used as antibiotics to fight bacterial infection.
  • In yeast
  • Can cause disease in plants, animals and humans
  • Ruin ¼ of fruits and vegetables harvested annually
  • Eats dead plants and tissues of living plants and animals
  • Don’t move other than growing
Protists
  • Eukaryotes
  • Some algae morph with fungi to from lichen…
  • Four main types: water molds, slime molds, protozoa and algae

Microbial Mergers:

Microbes can merge with other plants or cells or microbes. Here are some examples:

Algae can live in coral polyps and help the coral mimic the process of photosynthesis by converting sunlight into nutrients. It helps build the coral’s hard shell and supplies much of its energy. In return it gets a stable environment to grow.

About 50,000,000 years ago, Ants started to farm Fungi. This means that the ants clean, and provide food for the fungi, and the fungi helps the ants digest leaves and roots. Ants make the Fungi gardens in big, underground nests, that are safe for the fungi. Fungi Reproduction- The queen ant brings fungi with them when they move and mate.
Lichen- An Algae merged with a fungi. Fungi feed by absorbing, and Algae uses photosynthesis. Together they can live in places most things can’t live in- up to 20,000 species. Fungi give size and shelter. Algae gives food and nutrients. Fungi do more work
eats 60% of food. Lichen like sponge- retains lots of water and lets in out slowly.
Cell’s organelles- perform special functions just like the heart and lungs. Mitochondria- energy factories in each cell of fungi, protozoa, insects and animals. Chloroplasts- similar function in cells, algae and some protozoa. These Organelles are absolutely essential to life. Mitochondria & Chloroplasts and bacteria cells have similar appearances. These two organelles contain their own DNA or gene set, organized very much like the DNA in bacteria. They reproduce independently from cells they are in.
Mouthless Gutless Worms

  • No sun at the bottom of the sea
  • Slender tubeworms live on the bottom of the ocean near hydrothermal vents
  • They have no mouth, stomach or intestines yet they thrive and grow up to 8 feet tall
  • They don’t eat because they house billions of bacteria that feeds them
  • Their tissues are lined with bacteria that convert hydrogen sulfide, from the hydrothermal vents, into molecules that serve as nutrients for the worms.
  • Their gills look like a red plum sticking out of it’s tube
  • It’s blood has special hemoglobin that transports sulfides, oxygen and carbon dioxide into it’s tissue where the bacteria turns it into food for it’s host and themselves
  • The worm provides the bacteria protection

Virus vs. Bacterium:
People confuse viruses and bacterium because they both cause diseases, but they are actually very different. Here are some differences:
Size- The biggest viruses are the size of the smallest bacterium.
The cells- The cells in bacterium are complicated. They have a rigid cell wall, and a rubbery membrane surrounding the cytoplasm. There is DNA in the chromosomes and also floating around in other parts of the cell. They also have ribosomes for copying DNA so that they can reproduce. Some have flagella, which is used to move.
The biggest difference between bacteria and viruses is the way they reproduce.
Reproduction:




Viral Reproduction

Bacterial Reproduction

1. Invade or get swallowed by other cells.

Has all necessary tools for reproduction.

2. Take over the machinery.



3. Reproduce within that cell.



4. The cell bursts.



5. The virus spreads and invades new cells.