Marijuana
| Marijuana |
|---|
|
| Scientific Classification |
|
| Subspecies |
|
 |
| A Cannabis plant in its habitat. |
Marijuana is the common name for species of the genus Cannabis. Cannabis is a fast-growing bushy annual that sprouts dense, sticky flowers, or what are called buds. Among the 400 other chemicals naturally produced when growing marijuana the most well-known is Tetrahydrocannabinol, the effects of which can be felt by smoking the buds after drying. Marijuana is a herbaceous flowering plant in which the stalks can be used to produce clothing and rope creating a whole industry of legal products. They are grown in abundance in America especially in the northwest areas and midwestern states such as Kansas and Nebraska. Cannabis can grow up to 20 feet and it reproduces sexually in its native habitats, however growers have found ways to speed up the reproduction process by forcing asexual reproduction.
Anatomy
Cannabis is an astounding herb that can grow to be 20 feet tall in a short period of four to six months. It is a flowering annual, which means that it will germinate, flower, and die in one year.[1] The leaves are palmately compound with serrated leaves.[2] Seeds that are planted in spring usually germinate within three to seven days. The hypocotyl, which will eventually develop into the stem, straightens and causes the seedling to emerge from the soil. The length of the hypocotyl will range from one to ten centimeters. The cotyledons, the seed leaves, are unequal in size; narrowing at the base and rounded at the tip. The first true leaves appear in a pair about ten centimeters or less above the cotyledons. The leaflets each possess a distinct petiole, rotated one-quarter turn from the cotyledons. Successive leaves arise in opposite formation. A variously shaped leaf sequence develops with the second pair of leaves having three leaflets, the third five, and so on up to eleven. Occasionally there will be alterations such as the first pair of leaves having three leaflets, which in turn affects the latter sets. If a plant is not too full, the limbs will grow from small buds, which are located at the intersection of the petioles, along the primary stem.
Cannabis plants are dioecious, meaning that each plant is either male, staminate, or female, pistillate. The male plant produces pollen, which then pollinates the flowers of the female plant. Once the female is pollinated, it will begin to produce seeds. At a young age, their curved claw shape can identify the male flowers. While young, females are recognized by the enlargement of a symmetrical tubular calyx, which is a floral sheath. As they grow older, the male flowers hang in loose, long, multi-branched, clustered limbs that can grow to be twelve inches long. The female flowers, however, are smaller and are found tightly crowded between small leaves. The female flowers appear as two long white, tallow, or pink pistils protruding from the fold of a very thin, membranous calyx. The calyx is covered with hairs called resin exuding glandular trichomes. Female flowers are borne in pairs at the nodes on each side of the petiole behind the stipule of bracts, reduces leaves, which conceal the flowers. The calyx can measure from two to six millimeters in length and completely contains the ovary. In male flowers, five petals, usually three sixteenths of an inch long, make up the calyx and can be yellow, white, or green in color. They hang down and have five stamens, at about five millimeters long, that are composed of slender anthers, splitting upwards from the tip and suspended on thin filaments. The exterior surface of the calyx is covered with non-glandular trichomes. The pollen grains are nearly spherical, slightly yellow, and twenty-five to thirty microns in diameter. Soon after dehiscence, pollen shedding, the male plant dies, while the female plant may mature up to five months after viable flowers are formed it little or no fertilization occurs. Male plants, when compared to females, show a more rapid increase in height and a more rapid decrease in leaf size to the bracts, which accompany the flowers. Male plants tend to flower up to one month earlier than pistillate plants; however, female plants often differentiate primordia one to two weeks before male plants. Before the process of flowering begins, the leaf arrangement, the phyllotaxy, reverses and the number of leaflets per leaf decreases until a small single leaflet appears below each pair of calyxes. The phyllotaxy also changes from opposite, decussate, to alternate and usually remains alternate throughout the floral stages regardless of sexual type. The surface is smooth and will exhibit two to four germ pores. Female plants tend to be shorter and possess more branches. The females are leafy on the top with many leaves surrounding the flowers, while male plants have fewer leaves near the top with few, if any, leaves along the extended flowering limbs. Sinsemilla, meaning “without seed”, is a female cannabis which has been specially raised not to produce any seeds. This is done by carefully removing all male plants before they are able to produce pollen. This is also done in an attempt to increase floral production, which increases THC production.[1]
Reproduction
Cannabis is most commonly reproduced sexually, however, it is not unheard of for a breeder to utilize asexual reproduction. Sexually, the male reproductive plant will shed pollen, which will then wind-pollinate the female reproductive plant. Germination occurs fifteen to twenty minutes after contact with the pistil. As the pollen tube grows, the vegetative cell remains in the pollen grain while the generative cell enters the pollen tube and migrates toward the ovule. The generative cell then divides into two gametes, or sex cells, as it travels the length of the pollen tube. Pollination of the female flower results in the loss of the paired pistils and a swelling of the tubular calyx where the ovule is enlarged. After approximately fourteen to thirty-five days, the seed is mature and drops from the plant, leaving the dry calyx attached to the stem. A hard mature seed is partially surrounded by the calyx and is variously patterned in gray, brown, or black. Elongated and slightly compressed, it measures two to six millimeters in length and two to four millimeters in maximum diameter.[1]
A breeder will begin attempting to clone a marijuana plant two months after germination. First, they will deprive the plant of nitrogen for about a week; this will speed up the rooting process. They then take cuttings from the bottom one-third of the plant. It is best for the specimens to be of young growth tips from a vegetative stage, mature plant approximately three to five inches long with a stem diameter of about one-fifth to one-tenth of an inch. The sample is then dipped in water and warmed, such as with a heating lamp or a hot pad. The cuttings will root within two to three weeks. The plant must then be fed rooting solution and plant food, but the most essential factor is to keep the plants moist.[3]
Ecology
In the U.S., Cannabis grows in abundance in mid-western states such as Kansas and Nebraska. Cannabis Sativa subspecies sativa shows a great deal of climatic variation. For example, in temperate regions, it can reach heights of twenty feet, but in colder regions, it may only reach one foot.
Most members of Cannabis are short-day plants, however, some are said to be day-neutral. This means that they do well in mild to moderately sunny areas where the days are not completely filled with sunshine.[4] If provided with an open sunny environment, light-well drained composted soil, and ample irrigation, Cannabis can grow to extreme heights. Exposed riverbanks, meadows, and agricultural lands are ideal habitats for Cannabis since all offer good sunlight. Under favorable conditions, Cannabis grows up to seven centimeters a day. The time taken to form primordia varies with the length of the inductive photoperiod. Given ten hours per day of light, a strain may only take ten days to flower, but if there are sixteen hours of sunlight per day, it may take up to ninety days. Inductive photoperiods of less than eight hours per day do not seem to accelerate primordia formation. Dark cycles must be uninterrupted to induce flowering.[1]
Drug Use
Today, marijuana is the most widely used illegal drug in America. Tetrahydrocannabinol, or THC is the major draw for Americans as well as peoples worldwide. It is a euphoria inducing drug that can be seen covering marijuana buds in a white color, appearing as crystal-like structures. It is therefore concluded by the drug user that the more THC a particular bud can be seen to have the better the high will be. Marijuana is most commonly smoked after these already manicured and dried then purchased buds have been broken down by hand or scissors and rolled within a thin paper; it is then called a, "marijuana cigarette," or joint. The process is similar to that of rolling a tobacco cigarette.
Common low-grade marijuana has an average of 3% THC. Sinsemilla, considered high-grade marijuana has an average of 7.5% THC but can be as high as 24%. Hashish (hash) is derived from the sticky resin of the female plant flowers, can also be smoked in pipes however and has an average of 3.8% THC content with a range peaking at around 28%. Hash oil, a tar-like liquid distilled from hash, has an average of 16%, with a range as high as 43%.[5]
The initial effects of the drug fade after two to three hours, but can peak usually 20 minutes after deep inhalation. The remnants of THC can remain in the user's body for up to a month depending on the amount, potency and how long the use of the drug per day lasted. A first time user would typically experience, albeit in a more sustained and heightened fashion compared to a seasoned smoker, dry mouth, rapid heartbeat, a loss in coordination of basic motor skills and articulation of thoughts, difficulty approaching complex tasks, an alteration of both how fast time passes and sensitivity of their senses, as well as expanding blood vessels, laughing fits and an urge to eat.[5]
Marijuana use is indeed harmful in other ways. Short-term memory loss may become a problem if heavy, daily consumption happens over an extended period of time and any act of inhaling any type of smoke substance into your lungs over a long period of time is extremely harmful to your respiratory system.[6]
Medical use
There has been much debate in the media about the possible medical use of marijuana. THC, in the form of a pill, can be used for treating the nausea and vomiting that go along with certain cancer treatments and is available by prescription. The Food and Drug Administration has also approved another chemical related to THC, nabilone, for treating cancer patients who suffer nausea. Oral THC is also used to help AIDS patients eat more to keep up their weight.[5]
Gallery
Cannabis Sativa seeds
Marijuana
(Cannabis sativa)
A man holding a tulip, a sack of marijuana attached to a joint
people protesting marijuana legalization
References
- ↑ 1.0 1.1 1.2 1.3 Marijuana Botany Robert Connell Clarke
- ↑ Cannabis May 18, 2009, Wikipedia
- ↑ Cloning Cannabis Perfect Marijuana
- ↑ Wild Cannabis Wikipedia.
- ↑ 5.0 5.1 5.2 THC October 10, 2002, Psychology Today Staff
- ↑ The Associated Press. Calif regulators find pot smoke causes cancer. 19 June 2009. The Sacramento Bee.
- USDA-Cannabis USDA.gov
- Male and Female plants AmsterdamWebConnection
External links
- The endocannabinoid system as a target for the treatment of cannabis dependence By Jason R. Clapper, Regina A. Mangieri, and Daniele Piomelli Neuropharmacology. Author manuscript; available in PMC 2010 January 1.
- Cannabis withdrawal in the United States: a general population study By Deborah S. Hasin, Katherine M. Keyes, Donald Alderson, Shuang Wang, Efrat Aharonovich, and Bridget F. Grant ; J Clin Psychiatry. Author manuscript; available in PMC 2009 November 16.
- Negative consequences associated with dependence in daily cannabis users By Alison Looby and Mitch Earleywine ; Subst Abuse Treat Prev Policy. 2007; 2: 3. Published online 2007 January 10.
- DSM-IV Substance Abuse Criteria By Dawn Farm
- Heavy Marijuana Use Doesn't Damage Brain-Analysis of Studies Finds Little Effect From Long-Term Use By Sid Kirchheimer; WebMD Health News; July 2003
- Emotional Intelligence And The Use Of Tobacco And Cannabis By ScienceDaily; November 2007
- Cannabis The Vaults of Erowid
