The Dutch naturalist who, known as the Father of Microbiology, was the first person to observe protozoa and make written records of his observations.

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The what are protozoa that move using a flagellum, a long, whip like organ of locomotion.

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Generally, what are found in freshwater lakes, ponds, and streams.

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The what, an elastic "holding tank" that collects and disposes of excess water, is also located near the reservoir.

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The what of the genus Trypanosoma is a parasitic flagellate that moves using two flagella.

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Perhaps the best known of the what the protozoa that move by means of pseudopods, or "false feet" is the what.

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As the pseudopods enclose the particle, a portion of the amoeba's cell membrane forms the lining of a what within the amoeba.

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The what, members of the genus Paramecium, are distinguished by their unique slipper shape and by the cilia that completely cover them.

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The what whose body is shaped like an upside down bell, is often found attached by a stalk to an underwater object in stagnant pond.

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The what, named after a Greek herald in the Trojan War, is trumpet shaped ciliate that can grow to a length of 3 mm and can be found swimming freely in fresh and salt water.

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Almost all of the spore forming protozoa, or what, are incapable of independent movement and exist as heteroecious parasites.

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The five species of the parasite what that cause the widespread tropical disease malaria in humans are typical sporozoans.

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Plants, animals, fungi, and protozoa are what, organisms with organized nuclei.

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Blue green algae, which have a different cellular structure than other algae, are usually classified with bacteria in separate group called what, single celled organisms that have no organized nuclei.

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What live in the air, soil, and water, as well as in the bodies of other organisms.

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One oof best known species of bacteria is Escherichia coli, or simply what.

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The what are particularly hardy prokaryotes.

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A what is a tall, perennial, woody plant with a single main stem, or trunk, that divides into smaller stems called branches.

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A woody plant that has several equally large stems instead of a single main stem is a what.

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The top portion of a tree, which includes the branches and leaves, is the what.

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Trees are either angiosperms or gymnosperms; angiosperm trees, which reproduce by seeds formed in flowers, are called what because their leaves are broad and flat.

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Most broadleaf trees in warm regions are what, losing their leaves in the fall and staying bare all winter.

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Many gymnosperms are what, because unlike deciduous angiosperms, they keep their leaves during the winter.

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What, the most common gymnosperms, are named for their cone shaped reproductive structures.

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Conifers produce both male and female what.

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The tallest trees are the what, which commonly reach heights of 61 to 91 m.

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What, found in the western United States and Canada, are the second tallest trees.

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Another tall tree is the what.

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However, the oldest known organisms on the planet are the what found in California's White Mountains.

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What are a unique variety of slow growing, palm like gymnosperms.

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The what is a unique species of Oriental gymnospermssperm; it has short branches and fan shaped leaves that turn bright yellow and fall quickly in autumn.

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Although seldom seen, what are an important part of the tree.

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What are similar to fibrous root found on herbaceous plants; the primary difference is the roots' diameters.

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The main stem of a tree is the what.

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What is the rough outer covering of a tree.

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A ring of growth cells called the what separates the bark layers from the woody tissue of the trunk.

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This growth of a stem in diameter is called what.

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What is the main tissue of the trunk.

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Each year, the wood produced by the vascular cambium forms in layers called what.

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The central core of a young woody stem is called what.

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This hard, inactive dead wood is called what.

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The functioning wood surrounding the dead heartwood is called what.

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Besides the trunk, the stem of a tree includes smaller divisions called what.

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At the end of a twig and on the sides of the twig, there are small what.

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The what, found at the end of a twig, allows the stem to grow in length.

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The growth in length is called what.

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What on the sides of the twig allow the stem to produce new branches.

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What vary by location on the plant and by the habitat of the plant.

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The what is a waxy protective layer on leaf that encourages water retention.

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What are at the bottom of the tree.

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As seasons change, the leaf sends its leftover nutrients and sugars back into the stem before the what forms.

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All that remains on the tree is a what.

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A what is a dance collection of trees with a thick top layer of interlaced leaves called the canopy.

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An what shows no significant signs of major disturbances, such as the effects of a severe natural disaster or of being used for timber.

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A forest that grows up from unforested land is a what.

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A what is a limit beyond which these factors are unsuitable for tree growth.

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The what is divided into the northern coniferous forest and the northern hardwood forest.

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The what, also called the southern oak pine forest, stretches across southeast America from Delaware to Florida and west to Oklahoma and Texas.

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Along the Mississippi River is the what.

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Covering 19 million hectares of northern California, Oregon, and Washington and parts of Canada and Alaska is the what.

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The what extends from Canada into Mexico.

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The last forest region in Northern America is the what.

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What, the science of managing and studying forests and related natural resources, has helped to restore the forest.

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