Human uses of..
1.1
Leaves
1.2
Stems
1.3
Roots
1.4
Self Quiz
1.5
References
Humans have many uses for plants. They provide us with food, wood and paper products, fibres, fuels, and medicines with the use of their leaves, stems, and roots.

1.1 Humans uses of Leaves

Leaves contain importent nutrients and energy which are seen in the diets of humans and our livestock. Especially dark gren leafy vegetables, such as spinach are especially nutritous. Contaning importent minerals such as Calcium, potassium, iron, and magnesium, as well as vitimans B, C, E, and K. Also provide nutrients that protect our cells from damage, such as beta-carotene, lutin, and zeaxanthin. Other then food and culture, Humans have found uses of the waxy cuticle of leaves as well. Examples such as wax produced by carnauba palm leaves is used to make car and furniture polishes. it is also used for surfboard wax.
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1.2 Human uses of Stems


The most obvious human use of stems is in many wood-based products we use, such as furniture, to kitchen cabinetry, to the paper in books. Humans use vascular plant stems and the chemicals they contain, for a variety of other purposes (see table below )

Fuel
- ethonal
- wood
Dyes
- indigo, used to dye jeans
- hematoxylin, a stain used to prepare microscope slides
Food
- sugar cane
- potatoes
- yams
- maple syrup
- asparagus
Other Chemicals
- tannin, an ingredient in wood stains
- turpntine, a solvent
- latex rubber, used for many products including gloves,
tubing, and erasers
Textiles
- flax
- hemp
- bamboo
Medicine
- salicylic acid, a pain reliever made from willow bark
- taxol, an anti-cancer drug made from the bark and neddles
of yew trees
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1.3 Human uses of Roots


As with leaves and stems, humans have found many more ways to benifit from the diversity amoung roots of vascular plants. We use roots as food, for ourselves and our livestock, and as a source of useful chemicals. Many of the vegetables we eat are roots, such as parsnips, turnips, beets, taro, and sweet potatoes. Roots may also be used to make beverages, for example root beer. There are also many uses for the wide variety of chemicals produced by roots. Some roots can be used to dye textiles, pesticides such as rotenone come from the pea family, which protects them from being eaten by unwanted insects. As with some leaves and stems, roots of some plants produce chemicals for medicinal purposes. such as the Ipecac, a substance that may be given to someone who has swallowed something poisonous. It will rapidly reduce vomiting and prevent any further absorbtion of the poison. as with this root, there are other plant roots being used for medicinal research.

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1.4 Self Quiz

1. List off at least 2 uses of the waxy cuticle of leaves
2. Taxol, an anti-cancer drug made from the bark and neddles
of which tree?
- Oak - Pine
- Yew - Birch
3. Rotenone is a natural pesticide made by the " " family
4. This chemical substance will rapidly reduce vomiting and prevent any further absorbtion of poison

1.5 References

1. Dulson J, Fraser D, LeDrew B, Vavitsas A. Biology 11. University Preparation. Toronto: Nelson; 540-561.