The manipulated variable was the type of soil used in this experiment.  One variable was soil that had been previously sterilized.  The second variable was soil that was native and was expected to have fungal spores in it.
The responding variable was the height of the plant and the number of leaves the plant had.  The length was measured in centimeters from the top of the soil to the tip of the longest leaf.  Any plant which turned brown in color or was unable to stand up on it’s own was considered dead.  The number of leaves on the plant were counted by eye.  Any growth from the plant longer than 2cm was counted as a new leaf.

PLANTS
 A plant is any member of the plant kingdom.  The 260,000 known species include mosses, ferns, bushes, vines and others.  Plants vary in size, shape, color, and lifestyles.  Although it may seem like it, only a small percentage of plants are used directly by humans as either food, shelter, drugs, or fiber.  Even though that is true, for billions of years, plants have provided the atmosphere with oxygen ,which is necessary for life.
 The most distinct and different feature of a plant is the cell wall. The cell wall protects the cell’s contents and limits the growth of the cell.  It absorbs, transports and secretes, along with making the cell self-efficient. Cellulose is the main “ingredient” of the cell wall, and is made of molecules of the sugar glucose.  Fibril forms the structural frame work of the wall.  Lignin add  rigidity, and waxes reduce water loss from cells.  Just inside the cell wall is the cell membrane which is selectively permeable, making a great seal for the cell.  Communication with nearby cells is possible through the plasmodesmata.
 Inside the cell wall are living contents called protoplast.  The protoplast contains cytoplasm , a semifluid that fills the cell, which contains membrane-bound organelles, vacuoles and nucleus. An organelle is a structure which carries out a specialized function in the cell.  Vacuoles are membrane-bound cavities that have cell sap.  Cell sap contains water and dissolved sugars, salts, and other chemicals.  The nucleus stores genetic information which is passed on during cell division.  It is bound by a nuclear membrane which separates it from the rest of the cell.  The nucleolus is inside the nucleus membrane.         (Figure 1)      The function of the nucleolus is producing ribosomes.  Ribosomes are responsible for making proteins.
 Endoplasmic reticulum are extensive networks of tubes.  There are two types of
endoplasmic reticulum.  The first is rough endoplasmic reticulum.  This has ribosomes attached to the outside of it.  The proteins made by the ribosomes are transported through the rough endoplasmic reticulum to either the Golgi apparatus(which stores, packages, or distributes the
proteins and lipids produced by the endoplasmic reticulum) or regions of the cell where the it is needed.  The second type is smooth endoplasmic reticulum.  This has a smoother look because of the lack of ribosomes.  It is involved in the synthesis of lipids which make up the cell membrane along with the membrane of other things such as the mitochondria.
Mitochondria  change food material into an energy source called adenosine triphosphate.  This process takes place in the folded inner membrane called cristae.  The outer membrane of the mitochondria lets materials in and out of the structure.
 Organelles are another difference between animal and plant cells.  Plastids are types of organelles.  Photosynthesis occurs in chloroplasts which contain chlorophyll and carotenoid pigments. Both chlorophyll and carotenoids are involved in the absorption of light for photosynthesis and the coloring on the plant. Leucoplasts don’t contain any pigments, and are involved in the synthesis of starch, oils, and proteins.  Chromoplasts make carotenoids.  Last encased in the cell are lysosomes.  These are capable of breaking down complex molecules in the body.

PHOTOSYNTHESIS
 The most distinguishing characteristic of a plant is its ability to photosynthesize.  Some plants are unable to photosynthesize, but other characteristics in their structure show they are plants.  Photosynthesis is the process by which green plants and some other organisms use the energy of light to create simple sugar glucose.  An important byproduct of photosynthesis is oxygen.  Millions of new glucose molecules are produced by the second.  This glucose is used as an energy source to build leaves, flowers, fruits, and seeds.  It is also converted into cellulose which is in cell walls.  Most plants produce more glucose than is needed and store it and other carbohydrates in roots, stems, and leaves.
 Humans and other animals depend of glucose as energy too. They are unable to produce it themselves so they depend on plants for it.  The oxygen animals breath everyday is also produced by plants.
 The process of photosynthesis takes place in chloroplasts, found in leaves and green stems. Every cell has 40 to 50 chloroplasts. Inside chloroplasts are disk-like compartments called thylakoids. Embedded in the membranes of the thylakoids are hundreds of molecules of chlorophyll.  Chlorophyll is a light-trapping pigment which is required for photosynthesis. Other molecules needed for photosynthesis are also located in the thylakoid membranes.
      (Figure 2)
CARROTS
Daucus carata, or carrot, varies in color from
orange and yellow to white and purple-fleshed.  A bright orange color means high carotene content.  Carrots are native to Afghanistan and other neighboring lands.  They were cultivated even before the Christian era, and were in China and northwest Europe by the 13th century.  Carrots are used as food for livestock and humans.  They provide carotene and other nutrients.  The edible taproot and attached roots are below the surface of the earth.  Ends of the main stalk and branches bear large compound bunches of tiny white or pinkish flowers.
The three most important elements in carrots are Vitamin A, Beta-Carotene, and phytochemicals.  Vitamin A helps skin, eyes, hair, growth, and it helps our bodies resist infections.  Vitamin A helps to keep normal cell reproduction.  Cancer is when cells don’t reproduce normally.  Therefore, cancers such as lung, breast, and prostate could possibly be helped by eating carrots or other sources of Vitamin A.  Beta-carotene is found primarily in dark green, red, yellow, and orange-colored plants.  It is linked to reducing cancer and heart disease or other chronic diseases. Vitamin A and beta-carotene are especially important in a woman’s diet.  It helps with premenstrual syndrome, vaganitis, and osteoporosis.   It can be converted into Vitamin A or it can work as itself.  Carrots are also a good source of fiber.  Fiber is linked to reducing cholesterol in our bodies. Carrots are good for your eyes also. Vitamin A and Beta-carotene can lower the risk of eye diseases,  such as night blindness and cataracts.  It also helps stomach problems like an upset stomach, peptic ulcers, and diarrhea.  Those three elements benefit our body by boosting immunity, especially among older people. Phytochemicals may reduce the risk of stokes, hinder aging processes, balance hormonal metabolism, and have antiviral and antibacterial properties. Some other reasons carrots help the body are:
Beta-carotene protects the skin from sun damage
Eases alcohol withdrawal symptoms
Improves symptoms of HIV
Vitamin A keeps cell membranes healthy, making then stronger against disease-causing microorganisms
Helps to heal minor wounds and injuries
Reduces acne
Improves muscle, flesh, and skin health
Reduces the risk of heart diseases and the risk of high blood pressure.

SEEDS
The typical seed contains the embryo (undeveloped plant), the endosperm (stored food), and the many protective layers.  The embryo itself consists of the plumule (seed bud), and the epicotyl (stem) that form the undeveloped stem.  The cotyledon or cotyledons are the leaves, and the hypocotyl connects the cotyledons.  Last encased in the embryo is the radicle, which is the undeveloped root of the seed.  The embryo varies greatly in size and form, depending on the seed.  At germination, the plumule develops into the shoot (part of the plant above the ground).  The radicle develops into the root of the plant.  Cotyledons, in the seed, may or may not appear above ground.  In the hypocotyl area of the embryo axis, the change from stem to root tissue of the plant takes place.
The food, which is stored in the seed, is used as the plant’s source of energy.  It is used for the early development and germination of the seedling.  The seed’s nutrition is also used for humans and animals.  It includes carbohydrates, fats, and proteins.  Mineral matter and other accessory foods are also included. Some seeds even have ingredients found in medicines.
 

ROOTS
 Roots have many uses.  They anchor the plant and absorb water, air, and minerals that plants need for development.  They are at least the length of the above ground part of the plant.  The roots may have more branches than the number of shoot branches above ground.
 In the taproot system, the taproot is a long, primary root that is larger than the rest of the roots.  Another root system other than the taproot is the fimrous system.  This system has a short, almost unnoticeable primary root and many secondary roots.  Carrots have a taproot and the taproot is edible.
The roots originate from the embryo of the seed.   This has a root cap and an inside region of growth called the apical meristem (left  below).   Cell divisions   (Figure 3)       and cell elongation make for the lengthening of the primary root.  The roots of many plants grow in length and not in width, though the carrot does both.  The secondary roots grow out of tissues from the primary root.  The structure of the cells from the roots continues through the stem, though they differ in pattern.  The epidermis (outer layer) absorbs the nutrients and water with cellular extensions called root hairs.  Inside, the cortex stores food and water, the xylem transports the water, and the phloem transports the food.

        STEMS
The stem of the plants are above the ground.  They grow upward and bear leaves which are attached.  The leaves are  (Figure 4)         attached to the nodes along the stem.  The spaces in-between the nodes are called interodes.  Some stems are underground and are used as food-storage organs, which allow the plant to survive through the winter.  Tulips are a good example of this kind of stem.

LEAVES
Although sometimes the stem may photosynthesize, the leaf primarily does this job.  The leaf blades are usually flat and consist of a tissue called mesophyll.  Mesophyll is made up of loosely arranged cells which have spaces between them.  These spaces are filled with air that absorbs carbon dioxide and expel oxygen.  The mesophyll is bound by the epidermal tissue above and below it.  A vascular network runs through the mesophyll and provides the cell walls with water and removes food products. The food products are from photosynthesis and are transported to the various parts of the plants.  A leaf is connected to a stem through a petiole, or stalk, that is mostly vascular tissue.  Leaves can also be found below the ground in a bulb.  Tulips and daffodils are good examples of this.

FUNGI
 Fungi have no plastids or green chlorophyll, though they have roots, stems, and leaves like common plants.  They are unable to make sugar from carbon dioxide and water.  Most fungi are made up of a mass of threads spreading over, or through their food.  The food can be dead or decaying animals or plants.  The fungi who feed on this are called saprophytes.  Fungi cannot trap sunlight to make food, so some may live as parasites on green plants or animals.  These fungi are called parasites.  Fungi can send up a fruiting body containing spores.  Spores are then released into the air and settle to grow into a new fungi.  The fruiting bodies come in many different forms.
 Fungi are divided into five groups: bacteria, slime molds, algae fungi, sac fungi, and club fungi.  Bacteria are the most common fungi.  Some of these single-celled plants cause disease, though some are useful.  Slime molds are gray or yellow masses similar to the white of an egg.  They live in dark, shady parts of forests.  Algae fungi are long threadlike structures called mycelia.  They are much like algae, another similar plant.  Mold is another algae fungi.  Sac fungi produce their spores in small sacs.  Yeast are characterized as a  sac fungi, along with some molds.  Club fungi have short stalks that bear four spores.

HYPHAE
The hyphae are threadlike filaments which are characteristic of most fungi.  It is a thin, tubular wall that is filled with protoplasm (a living matter).  They vary in size from 1/50,000 inch to 1/250 inch in thickness.  Their length is indefinite.  Hyphae grow by extending the tip into longer threads.
There are two main types of hyphae, coenocytic and cellular. The hyhpae’s walls are different depending on the species. Most hyphae are cellular, which is considered the higher evolutionary form between the two.  Cellular hyphae are divided into segments by septum.  Each segment may contain one or two nuclei.  Coenocytic hyphae can have crosswalls like the cellular.  The difference is each segment would contain many nuclei. The protoplasm in the hyphae is made up of cytoplasm and nuclei.

WHAT IS MYCORRHIZAE?
In 1885, a German forest pathologist named A.B.   (Figure 5 )
Frank applied the name mycorrhizae to the fungus-tree relationship.  Ever since then, we have learned that an estimated 95% of all plants characteristically have a mycorrhizal symbiosis.
Mycorrhizae is the symbiosis between a fungus  hyphae and a living plant root.  Mycorrhizae literally means plant-root.  This partnership must be between two living organisms.  Fungi can harm the host, it can feed from the host without any benefits to it, or it can be mutual.  Mycorrhizal symbiosis are mutual relationships.  The two types of mycorrhizae are ectomycorrhizae and endomycorrhizae.
Ectomycorrhizae covers the tips of the tree roots (see figure 5).  Some of the hyphae spread into the root cells, and others spread from the roots into the soil. This creates a path from the soil to the tree so it obtains its nutrients.  In return, the fungi receive carbohydrates.  Many trees have this symbiosis.  However, most partnerships are endomycorrhizal.  This doesn’t coat the root, only a few hyphae spread across the surface of the root. Any hyphae that enter the root also enter the root cells.  Elaborate networks of filaments, called mycelia, extend out into the soil.  Great benefits are brought to the host plant by helping the uptake of water and minerals (phosphorus especially).

BENEFITS OF MYCORRHIZAE
 Fungi cannot photosynthesize on their own.  This makes them unable to get the food they need.  The hyphae take up nutrients from the soil and give them to the plants roots.  They also increase the surface area of a plant’s roots, enabling it to get more nutrients.  This can improve the growth of  a plant tremendously, especially in nutrient poor or moisture deficient soils.  The fungi receives sugars and growth hormones in exchange for their nutrients.
 Some trees may not be able to grow properly in soil without the fungi needed, Orchids may die of this.  A plants’ roots with the fungi can take on a different look.  They typically don’t have root hairs because the fungi replace it.  The roots can also be thicker and more brown in color.

PRESSURE STEAM STERILIZER
 Steam is one of the best ways to kill microbes quickly.  It works by a large volume of steam condensing into a very small volume of water. Then more steam is drawn to replace it.  This method is excellent for penetrating fabrics, and some papers and plastic films.
 Sterilization failure is possible. This happens when air gets trapped in the material being sterilized so that is doesn’t escape. The air-steam then has a lower temperature than the surrounding, pure-steam, and doesn’t work as well.
 The gauges on the sterilizer are said to have a 2% to 3% accuracy level.  The first and last quarter of the dial have a 3% accuracy and the middle 50% of the dial have a 2% accuracy.

CHEMICALS
 Potassium hydroxide, or KOH, is a white solid used in the making of soap and is an important chemical reagent.  It dissolves in less than its own weight of water.
 Ink is a pigment used for writing, printing, or drawing.  Colors, consistency and composition depend on the purpose of the ink.  All inks contain a colorant, or pigment, and a liquid into which the colorant is dispersed.
 Vinegar is a sour condiment.  It is created by two microbial processes.  The first is alcoholic fermentation and the second is the oxidation of alcohol by a bacterium.

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Conclusion

Benjamin, Chester R.  “Fungus.” The Encyclopedia Americana. 1993 ed.

Fogel, Robert. “Mycorrhizae:plant-fungus partners.”  October 96.
http://botany.about.com/gi/dynamic/offsite.htm?site=http://www.herb.lsa.umich.edu/kidpage/Mycorhiz.htm (4 December 2000).

“Ink.” Microsoft Encarta Encyclopedia. Compact disc. 2000.

Lim, Daniel V. Microbiology. St. Paul: West Publishing co. 1987.

McCollum, John P. “Carrots.” Encyclopedia Americana. 1993 ed.

“Mycorrhizae.”  Encyclopedia Americana.  1993 ed.

“Potassium.” Microsoft Encarta Encyclopedia. Compact disc. 2000.

Stevens, K.J., Peterson, R.L. “The effect of a water gradient on the vesicular
 arbuscularmycorrhizal status of Lythrum salicaria L. purple loosestrife.”
 http://www.uoguelph.ca/botany/grads/kstevens/Water_gradient.htm (29
November 2000). Stidworthy, John.  Plants and Seeds. New York: Gloucester
Press. 1990.

St. John, Ted.  “Mycorrhizal Project.” [Online] Available email: Chorses2k@aol.com
 From tstjohn@cosmoaccess.com.

Sylvia, David. “Overview of Mycorrhizal symbiosis.” 14, October 2000.
 http://dmsylvia.ifas.ufl.edu/mycorrhiza.htm (29 November 2000).

“The root of the Matter.” August 98.
 http://specials.about.com/service/ads/pop/spedia_2.html (29 November 2000).

Torrey, J.G. “Roots.” Microsoft Encyclopedia Americana.  1993 ed.

“Vinegar.” Microsoft Encarta Encyclopedia. Compact disc. 2000.

Pictures

(Figure 1)  “Plant Cell.”  Encarta 2000. Compact disc.  1999.

(Figure 2)  Kindersly, Dorling. “Cultivated Carrot.” Encarta 2000. Compact disc.
1999.
 

(Figure 3)  Teason, James., Moran , Margaret Ann. “Roots.” World Book 2000.
 Compact disc.  1999.
 

(Figure 4)  Walker. “Root tip showing apical meristem.” Encarta 2000. Compact
 disc. 1999.

(Figure 5)  Fogel, Robert. “Mycorrhizae:plant-fungus partners.”  October 96.
http://botany.about.com/gi/dynamic/offsite.htm?site=http://www.herb.lsa.umich.edu/kidpage/Mycorhiz.htm (4 December 2000).