Key Vocabulary Terms

Methane - a gas produced by bacteria from hydrogen and carbon dioxide.
Binary fission - Reproduction in which bacterial cell divides into two cells that look the same as the original cell.
Saprophyte - an organism that decomposes dead organisms or waste matter
Mutualism - a closeness in which two organisms live together and help each other
Commensalism - a relationship in which one organism benefits and the other is not affected.
Toxin -a poison produced by bacteria or other organisms
Endospores - Bacteria that dry up and form into cells with thick walls.

Key Concepts

Bacteria are single-celled organisms that are usually much smaller than other organisms. Bacteria cells lack organelles that are found in the cells of other organisms.
Most bacteria are shaped like rods, spirals, or spheres.
Bacteria may break down the chemicals in dead organisms, capture the energy in sunlight, or obtain energy from minerals.
Bacteria reproduce by dividing Minot two cells that look the same.
Bacteria are useful to humans in many ways; (bacteria help to produce foods, vitamins, antibiotics, and special chemicals.

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Diatom - Microscopic alga that has a hard shell
Paramecium - a protozoan that moves by using its hairlike cilia (plural is paramecia)
Trypanosome - a protozoan that is a parasite and lives in blood; may cause sleeping sickness.
Sporozoan - A protozoan that is a parasite and lives in blood; may cause malaria

Key Concepts

Unlike bacteria, the cells of protists have organelles.
Aquatic algae produce nearly half of the world's carbohydrates and oxygen.
Diatoms are single-celled algae with hard shells. Kelps are large, many-celled algae
Protozoans move by thrusting out pseudopods, bending their celia back and forth, or using flagella to push or pull themselves around.
Malaria is caused by a sporozoan. Mosquitoes spread malaria when they draw blood from an infected person and then bite other people.

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Gullet - the opening through which a paramecium takes in food.
food vacuole - a bubble like structure where food is digested inside a protozoan
Anal pore - the opening through which undigested food leaves a paramecium
Osmosis - the movement of water through a cell membrane
Contractile vacuole - a structure in a protist that removes water that is not needed
Eyespot - a structure on many protists that senses changes in the brightness of light.
Asexual reproduction - reproduction that involves one parent and no Jeff or sperm
Sexual reproduction - reproduction that involves two parents, and usually an egg and sperm

Key Concepts

Food enters the gullet, is enclosed in a food vacuole, and travels all through the paramecium; food waste is expelled through the anal pore.
Water continually enters a protist by osmosis. Without a means of removing the water, the protist would swell and burst.
Living in fresh water is difficult for single celled protists because water is entering the protist by osmosis and is not being expelled; eventually the protist bursts and dies.
By sensing changes in the brightness of light, eyespots allow algae to move to areas where the light is brighter. With brighter light, they can make food more quickly.
A single-celled protist reproduces asexually by dividing into two cells.

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Hyphae - thin, tubelike threads produced by a fungus
Mycelium - a mass of hyphae (plural is mycelia)
Cyclosporine - A drug that is produced from mold and that helps prevent the rejection of transplanted organs
Aflatoxin - a chemical that causes liver cancer and is produced by molds growing on stored crops.

Key Concepts

Fungi do not move from place to place as most animals do. Fungi cannot make their own food as plants do.
The gills of a mushroom release millions of spores into the air.
The hyphae make bread mold look fuzzy.
fungi break down waste matter and return nutrients to the soil.
Fungi cause ringworm and athlete's foot; they also cause allergies in some people.

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Investigation 5 "Growing bread mold" (Optional, must complete 10 total investigations)

Key Concepts and Objectives

You will use your skills of observing, classifying, describing, comparing, and recalling facts to find out how environmental conditions affect the growth of mold.
You will develop an organized chart that will help you determine the best growing conditions for mold.

Digestive - A chemical that helps break down food
Budding - reproduction in which part of an organism pinches off to form a new organism
Mycorrhiza - A mutualism between a fungus and the roots of a plant (plural is mycorrhizae)
Lichen - an organism that is made up of a fungus and an alga or a bacterium

Key Concepts

The function of digestive enzymes is to help brake down food.
Asexual reproduction in yeasts occurs when part of a yeast cell pinches off to make a smaller cell, which rapidly grows to the size of the first cell.
When a plus hypha touches a minus hypha, the two can join and form a structure that releases spores. the spores produce mycelia that are different.
Mycorrihiza is a mutualism between a fungus and the roots of plant
Lichens can be killed by air pollution. The presence of healthy lichens usually means the air is clean.

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Chapter Summary and Review

See page 112-113

Chapter 5 Review answers are