Microbe Scavenger Hunt

Directions:

q       You are going to go online to find the latest information about microbes from the American Society for Microbiology at http://www.microbeworld.org/microbes/

q       Begin by clicking Meet the Microbes on the toolbar at the top of the page.

q       Follow the directions to move from one page to the next and answer the questions.

What is a Microbe?

1.      Microbes are ___________________ organisms so tiny that ________________ can fit into the eye of a needle.

2.      Microbe fossils date back more than ______________________ to a time when the earth was covered with oceans.

3.      Without microbes, we couldn’t _______ or __________.

4.      Microbes are in the _______ we breathe, the ____________ we walk on, the ______________ we eat – they’re even inside ______!

5. We couldn’t _____________ food without them – animals couldn’t, either.
6. Without microbes, plants couldn’t ___________, garbage wouldn’t ____________, and there would be a lot less _______________ to breathe.

Types of Microbes (Click Types of Microbes on the left-hand menu.)

1. Microbes can be divided into six main types:
   1. ___________________
   2. ___________________
   3. ___________________
   4. ___________________
   5. ___________________
   6. ___________________

Bacteria (Click Bacteria on the left-hand menu.)

1.      Bacteria consist of only a single ________________.

2.      Bacteria have been found that can live in temperatures above the _________________ point and in cold that would ____________ your blood.

3.      There’s even a species of bacteria – Deinococcus radiodurans – that can withstand blasts of radiation 1,000 times greater than would kill a human being.

Classification

1.      Bacteria fall into a category of life called the ____________________.

2.      Prokaryotes’ genetic material or DNA is not enclosed in a cellular compartment called the _______________________.

How Long They’ve Been Around

1. Bacteria are among the earliest forms of life that appeared on Earth __________ of years ago. 
2. Scientists think they helped shape and change the young planet’s environment, eventually creating atmospheric ______________ that enabled other, more complex life forms to develop.
3. Many believe that more complex ___________ developed as once free-living bacteria took up residence in other cells, eventually becoming the ___________ in modern complex cells.
4. The __________________ that make energy for your body cells is one example of such an organelle.

What They Look Like (Click What They Look Like on the left-hand menu.)

1. There are ____________________ of species of bacteria, but all of them are basically one of _______ different shapes.  Some are ________ or stick-shaped and called _______________.
2. Others are shaped like little balls and called _____________.
3. Others still are helical or _________________ in shape, like the Borrelia pictured at the top of this page.
4. Some bacterial cells exist as _________________while others ____________ together to form pairs, chains, squares, or other groupings.

Where They’re Found (Click Where They’re Found on the left-hand menu.)

1. Bacteria live on or in just about every __________________ and environment on Earth from soil to water to air, and from your _____________ to arctic ___________ to ________________ vents.
2. Each square centimeter of your skin averages about ____________________ bacteria.
3. A single teaspoon of topsoil contains more than ____________________ bacteria.

What They Eat (Click What They Eat on the left-hand menu.)

1. Some bacteria are __________________________ - they can make their own food from sunlight, just like plants.
2. Also like plants, they give off ____________________.
3. Other bacteria absorb food from the material they live on or in.  Some of these bacteria can live off unusual “foods” such as ______________ or sulfur.
4. The microbes that live in your gut absorb __________________ from the digested food you’ve eaten.

How They Move (Click How They Move on the left-hand menu.)

1. Some bacteria move about their environment by means of long, whip-like structures called _____________________.
2. Other bacteria secrete a ______________________ layer and ooze over surfaces like __________________.
3. Others are fairly ________________________.

Archaea and Other Extremists (Click Archaea on the left-hand menu.)

Types of Archaea

1. There are three main types of archaea:
   1. ___________________
   2. ___________________
   3. ___________________
2. Archaea look a lot like _________________.  So much so that until the late 1970s, scientists assumed they were a kind of “weird” bacteria.
3. Then microbiologist Carl Woese devised an ingenious method of comparing ______________ information showing that they could not rightly be called bacteria at all. Their genetic recipe is too different.

Classification

1. Archaeans are single-celled creatures that join bacteria to make up a category of life called the _______________________.
2. Prokaryotes’ genetic material, or DNA, is not enclosed in a central cellular compartment called the ________________.
3. Bacteria and archaea are the only ____________________.
4. All other life forms are _______________________________, creatures whose cells have nuclei.

Early Origins

1. Archaeans are among the __________________ forms of life that appeared on Earth billions of years ago. 
2. It’s now generally believed that the archaea and bacteria developed separately from a ___________ ancestor nearly 4 billion years ago.
3. Millions of years later, the ancestors of today’s eukaryotes split off the archaea.  So historically, archaeans are more closely related to _________ than they are to bacteria.

What They Look Like (Click What They Look Like on the left-hand menu.)

1. Some archaea look like little __________ or tiny balls, and some even get around like bacteria using long hair- or whip-like appendages called ________________ that stick out of their cell walls.
2. Like bacteria, archaea lack a true _________________.

Where They’re Found (Click Where They’re Found on the left-hand menu.)

1. Archaea comes from the Greek word meaning “_______________.”
2. An appropriate name, because many archaea thrive in conditions mimicking those found more than __________________ years ago.
3. Back then, the earth was still covered by oceans that regularly reached the boiling point — an extreme condition not unlike the __________________ vents and ______________ waters where archaea are found today.
4. In addition to superheated waters, archaea have been found in acid-laden ____________ around old mines, in frigid _________________ ice and in the super-salty waters of the ______________________.    

What They Eat (Click What They Eat on the left-hand menu.)

1. Archaeans dine on a variety of substances for energy including _______________ gas, carbon _________________ and sulfur.
2. One type of salt-loving archaean uses _________________ to make energy, but not the way plants do.
3. This archaean has a light-harvesting pigment in the ________________ of its cell.
4. This pigment, called ____________________, reacts with light and enables the cell to make __________, an energy molecule.

Viruses (Click Viruses on the left-hand menu.)

What They Are

1.      A virus is basically a tiny bundle of _________________ material - either DNA or _____ - carried in a shell called the viral coat, or ______________, which is made up of bits of protein called _______________.

2.      Some viruses have an addition layer around this coat called an _____________.

3.      Viruses can’t metabolize ______________, produce and excrete wastes, move around on their own, or even ______________ unless they are inside other organisms.  They aren’t even _____________.

4.      Viruses have been the culprits in many human _____________, including smallpox, flu, _________, certain types of cancer, and the ever-present ___________________.

Single-Minded Mission

1. Viruses exist for one purpose only: to _______________________.
2. To do that, they have to take over the _______________ machinery of suitable host cells.
3. Upon landing on an appropriate _________ cell, a virus gets its genetic material inside the cell either by tricking the host cell to pull it inside, like it would a ________________ molecule, or by fusing its viral coat with the host cell wall or membrane and releasing its __________ inside.
4. If the virus is a ________ virus, its genetic material then inserts itself into the host cell’s DNA.  If the virus is an ________ virus, it must first turn its RNA into _________ using the host cell’s machinery before inserting into the host cell.
5. The viral _________ are then copied many, many times, using the machinery the host cell would normally use to _____________ its own DNA.
6. The virus uses the host cell’s enzymes to build new viral capsids and other viral ______________.

What They Look Like (Click What They Look Like on the left-hand menu.)

1. Viruses are the ______________ and tiniest of microbes; they can be as much as ____________ times smaller than bacteria.
2. There are _____________ of different viruses that come in a variety of shapes.  Many are _________________ or multi-sided.
3. Other viruses are shaped like spiky ovals or ___________ with rounded corners.
4. Some are like skinny ____________ while others look like bits of looping ___________.
5. Some are more complex and shaped like little lunar ____________________.

Where They’re Found (Click Where They’re Found on the left-hand menu.)

1. Viruses are found on or in just about every material and _________________ on Earth from soil to water to _______.
2. They’re basically found anywhere there are __________ to infect.
3. Viruses have _________________ to infect every form of life, from animal to plant and from fungi to ______________.
4. However, viruses tend to be somewhat picky about what type of cells they ___________.
5. Plant viruses are not equipped to infect _____________ cells, for example, though a certain plant virus could infect a number of related _____________.
6. Sometimes, a virus may infect one creature and do no harm, but cause havoc when it gets into a different but closely _______________________ creature.
7. True parasites, viruses are basically little more than molecular ______________ moving genetic information from one cell to another.