Tugas Bhs. Inggris : Middle Examination

Posted: 15th June 2012 by vaan in Uncategorized

 

Article :

What is the Transgenic Plant ?

 

Transgenic plants are plants that have been genetically modified by inserting genes directly into a single plant cell. Transgenic crop plants modified for improved flavor, pest resistance, or some other useful property are being used increasingly.

Transgenic plants are unique in that they develop from only one plant cell. In normal sexual reproduction, plant offspring are created when a pollen cell and an ovule fuse. In a similar laboratory procedure, two plant cells that have had their cell walls removed can be fused to create an offspring.

  • Ø Genetic Engineering Techniques

There are three general approaches that can be used to insert the DNA into a plant cell: vector-mediated transformation, particle-mediated transformation, and direct DNA absorption. With vector-mediated transformation, a plant cell is infected with a virus or bacterium that, as part of the infection process, inserts the DNA. The most commonly used vector is the crown-gall bacterium, Agrobacterium tumefaciens. With particle-mediated transformation (particle bombardment), using a tool referred to as a “gene gun,” the DNA is carried into the cell by metal particles that have been accelerated, or “shot,” into the cell. The particles are usually very fine gold pellets onto which the DNA has been stuck. With direct DNA absorption, a cell is bathed in the DNA, and an electric shock usually is applied (“electroporation“) to the cell to stimulate DNA uptake.

In earlier times, new plant varieties containing the genes of two species were created through hybridization or cross breeding. However, such breeding was carried out between two related species. Modern biotechnology and genetic engineering incorporates genetic material from not only related, but also from unrelated species in order to create transgenic and genetically modified plants. Bt corn, Bt cotton and golden rice are some of the common examples of plants created in this way.

No matter what gene insertion method is used, a series of events must occur to allow a whole genetically modified plant to be recovered from the genetically modified cell: The cell must incorporate the new DNA into its own chromosomes, the transformed cell must initiate division, the new cells need to organize themselves into all the tissues and organs of a normal plant (“regeneration“), and finally, the inserted gene must continue to work properly (“gene expression“) in the regenerated plant.

To help ensure all this occurs, a “cassette” of genes is inserted during the initial transformation. In addition to the gene coding for the desired trait, other genes are added. Some of these genes promote the growth of only those plant cells that have successfully incorporated the inserted DNA, for example providing the transformed cells with resistance to a normally toxic antibiotic that is added to the growth medium. Other genes (“promoters”) may be added to control the functioning of the trait gene by directing when and where in the transformed plant it will operate.

The genes put into plants using genetic engineering can come from any organism. Most genes used in the genetic engineering of plants have come from bacteria. However, as scientists learn more about the genetic makeup of plants (“plant genomics”), more plant-derived genes will be used.

 

 

 

  • Ø Agricultural Applications

Usefulness of inserted genes was those that protect a crop, those that improve the quality of a harvested product, and those that let the plant perform some new function.

  • Genes That Protect a Crop

The major use of plant genetic engineering has been to make crops easier to grow by decreasing the impact of pests. Insect resistance has been achieved by transforming a crop using a Bt gene. Bt genes were isolated from Bacillus thuringiensis, a common soil bacterium. They code for proteins that severely disrupt the digestive system of insects. Thus an insect eating the leaf of a plant expressing a Bt gene stops eating and dies of starvation. There are many Bt genes, each of which targets a particular group of insects. Some Bt genes, for example, target caterpillars. Others target beetles.

Genetic engineering also has been used in the battle against weeds. Bacterial genes allow crops to either degrade herbicides or be resistant to them. The herbicides that are used are generally very effective, but also must considered environmentally benign, degrading rapidly in the soil and having little impact on humans or other organisms. Thus a whole field of transgenic crops can be sprayed with broad-spectrum herbicides, killing all plants except the crops. Corn, soybeans, canola, and cotton that have been engineered to withstand either insects or herbicides, or both, are widely planted in some countries, including the United States. In addition, other crops, including potatoes, tomatoes, tropical fruits, and melons, have been engineered for resistance to viral diseases.

  • Genes That Improve Crop Quality

An emerging major use of genetic engineering for crops is to alter the quality of the crop. Fresh fruits and vegetables begin to deteriorate immediately after being harvested. Delaying or preventing this deterioration not only preserves a produce’s flavor, and appearance, but maintains the nutritional value of the produce. Genes that change the hormonal status of the harvested crops are the major targets for genetic engineering toward longer shelf-life.

For example, the plant hormone ethylene is associated with accelerated ripening, as well as leaf and flower deterioration, in fruits that are injured or harvested. This mean insert genes that interfere with a plant’s ability to synthesize or respond to ethylene, thereby extending postharvest quality for many fresh products, including tomatoes, lettuce, and cut flowers. Scientists are also using gene insertion to improve a plant’s nutritional value and color.

  • Genes That Introduce New Traits

One approach to improving the economic value of crops is to give them traits that are completely new for that plant. Some crops, including potatoes, tomatoes, and bananas, have been engineered with genes from pathogenic organisms. This is done to make animals, including humans, that eat the crops immune to the diseases caused by the pathogens. The genes code for proteins that act as antigens to induce immunity. Thus edible parts of plants are engineered to act as oral vaccines. This approach may be particularly effective for pathogens, such as those causing diarrhea and other gastrointestinal disorders, that enter the body through mucous membranes. This is because the “medicine” in the food comes into direct contact with these membranes and does not have to be absorbed into the blood stream. Genes have also been engineered into crop plants to direct the plants to produce industrial enzymes used in the manufacture of paper. Other genes direct crops to produce small polymers useful in the manufacture of plastics. This general approach is being termed “plant molecular farming.”

Rice is another plant that has been engineered for a new trait. During commercial processing, a substantial part of the white rice grains are removed, leaving very little vitamin A. Vitamin A deficiency is a significant health problem in regions dependent on rice as a dietary staple. Scientists engineered a certain form of rice, known as “golden rice” because it has a yellow tinge, to express three introduced genes. These genes let the plant produce the precursor of vitamin A in the portion of the grain that remains after processing, thereby providing a dietary source of the vitamin.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

REFERENCE

 

 

Anonymous. 2012. http://www.answers.com/topic/transgenic-plant.

Accessed at 13 April 2012.

 

CHAPTER II

A CLAUSE, SENTENCE, AND PHRASE

 

 

 

  1. A.    CLAUSE

A CLAUSE is a group of words containing a subject and a verb.

Example in paragraph 1:

Transgenic plants are plants that have been genetically modified by inserting genes directly into a single plant cell. Transgenic crop plants modified for improved flavor, pest resistance, or some other useful property are being used increasingly.

 

The analysis of which would be:

 

a)      Transgenic plants are plants that have been genetically modified by
 Subject                                                                   Verb
inserting genes directly into a single plant cell.
  

b)      Transgenic crop plants modified for improved flavor, pest resistance,

Subject                Verb
or some other useful property are being used increasingly.

 

  1. B.     SENTENCE

A SENTENCE may consist of one or more clauses.

Example in paragraph 10:

Genetic engineering also has been used in the battle against weeds. Bacterial genes allow crops to either degrade herbicides or be resistant to them. The herbicides that are used are generally very effective, but also must considered environmentally benign, degrading rapidly in the soil and having little impact on humans or other organisms. Thus a whole field of transgenic crops can be sprayed with broad-spectrum herbicides, killing all plants except the crops. Corn, soybeans, canola, and cotton that have been engineered to withstand either insects or herbicides, or both, are widely planted in some countries, including the United States. In addition, other crops, including potatoes, tomatoes, tropical fruits, and melons, have been engineered for resistance to viral diseases.

The analysis of which would be:

 

 

  • The herbicides that are used are generally very effective, but also must considered environmentally benign, degrading rapidly in the soil and having little impact on humans or other organisms.
    • The herbicides that are used are generally very effective.
    • The herbicides also must considered environmentally benign, degrading rapidly in the soil and having little impact on humans or other organisms.
    • Which are connected by the conjunction but.

 

The herbicides that are used are generally very effective.

Subject                      Verb

but

 

                                               

 

 

The herbicides also must considered environmentally benign,

   Subject                     Verb

degrading rapidly in the soil and having little impact on humans or other organisms.

 

 

 

 

 

 

 

 

 

 

  1. C.    PHRASE

A PHRASE is a group of words lacking either a subject or a verb.

Example in paragraph 6:

To help ensure all this occurs, a “cassette” of genes is inserted during the initial transformation. In addition to the gene coding for the desired trait, other genes are added. Some of these genes promote the growth of only those plant cells that have successfully incorporated the inserted DNA. It might do this by providing the transformed cells with resistance to a normally toxic antibiotic that is added to the growth medium, for example. Other genes (“promoters”) may be added to control the functioning of the trait gene by directing when and where in the transformed plant it will operate.

 

The analysis of which would be:

 

  • Adverbial phrase:

 

-          In addition to the gene coding for the desired trait, other genes are added. Some of these genes promote the growth of only those plant cells that have successfully incorporated the inserted DNA.

  • Verbal phrase:

 

-          To help ensure all this occurs, a “cassette” of genes is inserted during the initial transformation.

  • Adjectival phrase:

 

-          It might do this by providing the transformed cells with resistance to a normally toxic antibiotic that is added to the growth medium, for example.

 

  • Noun phrase:

 

-          Other genes (“promoters”) may be added to control the functioning of the trait gene by directing when and where in the transformed plant it will operate.

 


 

CHAPTER III

ABOVE THE CLAUSE:

CONTEXTUAL REFERENCE

 

 

In English, both general and academic, words like WHO, WHOM, WHICH, THAT, WHOSE, ABOUT, WHOM, TO WHICH, WHERE, WHEN,OF WHOM, OF WHICH and many more are used to refer to something that have been said before, or to what is going to be said.

Example in paragraph 2:

Transgenic plants are unique in that they develop from only one plant cell. In normal sexual reproduction, plant offspring are created when a pollen cell and an ovule fuse. In a similar laboratory procedure, two plant cells that have had their cell walls removed can be fused to create an offspring.

The analysis of which would be:

 

  • Transgenic plants are unique in that they develop from only one

 

plant cell.

  • In a similar laboratory procedure, two plant cells that have had

their cell walls removed can be fused to create an offspring.

 

 


 

CHAPTER IV

ABOVE THE CLAUSE:

PARALLELISM

 

 

 

  1. A.   PARALLEL STRUCTURE

 

One use of a conjunction is to connect words or phrases that have the same grammatical function in a sentence. This use of conjuctions is called PARALLEL STRUCTURE. The single conjuctions used in this pattern are, among others, AND, BUT, OR and NOR. They are also referred to coordinating conjunctions.

 

  1. B.   PAIRED CONJUNCTIONS

 

In section A above you are shown how single conjunctions can be used to join two or more clauses into one new sentence. In English you can find paired conjunctions carrying the same function as single ones. Some examples of paired conjunctions are:

  • BOTH …. AND ….
  • NOT ONLY …. BUT …. ALSO

 

 

Example in paragraph 8:

Usefulness of inserted genes was those that protect a crop, improve the quality of a harvested product, and let the plant perform some new function.


 

The analysis of which would be:

 

  • Usefulness of inserted genes was those that protect a crop
  • Usefulness of inserted genes was those that improve the quality of a harvested product
  • Usefulness of inserted genes was those that let the plant perform some new function


 

CHAPTER V

ABOVE THE CLAUSE:

TEMPORAL RELATIONSHIP

 

 

In a procedure text, teh description of processes makes use of words or phrases such as first[ly], then, the next step, the next stage, subsequently, finally to introduce each stage.

 

Example in paragraph 5:

No matter what gene insertion method is used, a series of events must occur to allow a whole genetically modified plant to be recovered from the genetically modified cell: The cell must incorporate the new DNA into its own chromosomes, the transformed cell must initiate division, the new cells need to organize themselves into all the tissues and organs of a normal plant (“regeneration“), and finally, the inserted gene must continue to work properly (“gene expression“) in the regenerated plant.

 

The analysis of which would be :

  • The cell must incorporate the new DNA into its own chromosomes, the transformed cell must initiate division, the new cells need to organize themselves into all the tissues and organs of a normal plant (“regeneration“), and finally, the inserted gene must continue to work properly (“gene expression“) in the regenerated plant.

Sentence above are connected by the conjunction finally

finally

 

 

 

 

 

CHAPTER VI

ABOVE THE CLAUSE:

CASUAL RELATIONSHIP

 

 

A writer may want to tell his readers or his audience that the preceding statement is the result of the result of the following one, or the other way around. He, therefore, needs to employ expressions such as “consequently”, “therefore”, “thus”, “as”, “since”, and “and so” to realize his intent.

 

Example in paragraph 7:

The genes put into plants using genetic engineering can come from any organism. Most genes used in the genetic engineering of plants have come from bacteria. However, as scientists learn more about the genetic makeup of plants (“plant genomics”), more plant-derived genes will be used.

The analysis of which would be :

  • However, as scientists learn more about the genetic makeup of plants (“plant genomics”), more plant-derived genes will be used.

-          Cause clause : However, as scientists learn more about the genetic makeup of plants (“plant genomics”).

-          Result clause : More plant-derived genes will be used.

 

 


 

CHAPTER VII

ABOVE THE CLAUSE:

CONTRASTIVE RELATIONSHIP

 

 

Two clauses can also be contrasted. To realize a relationship of contrast between two clauses in English, some special conjunctions are used. Expressions like “but”, “however”, “in contrast”, “while”, “on the other hand”, instead”, and “although” can be used to show that the information in one statement is the opposite of another.

-        Nevertheless

-        Nonetheless

-        On the contrary

-        Anyway

 

 

Example

The genes put into plants using genetic engineering can come from any organism. Most genes used in the genetic engineering of plants have come from bacteria. However, as scientists learn more about the genetic makeup of plants (“plant genomics”), more plant-derived genes will be used.

From the sentence above, we can take conclusion that:

 

  • The genes put into plants using genetic engineering can come from any organism. Most genes used in the genetic engineering of plants have come from bacteria.
  • as scientists learn more about the genetic makeup of plants (“plant genomics”), more plant-derived genes will be used.

The expressions of two sentences are  opposites of each other. The relationship between these two sentences is one of opposition.

 

however

 

 

 

CHAPTER VIII

ABOVE THE CLAUSE:

EXEMPLIFICATION

 

 

In trying to clarify his point of view, awriter may need to use examples of the theory he proposes. He may employ a conjunction signaling the exemplification.

Study how the conjunctions are used the realize the relationship of exemplification. Example expressions like “such as”, “for example”, “for instance”, “like”.

Example in paragraph 6:

To help ensure all this occurs, a “cassette” of genes is inserted during the initial transformation. In addition to the gene coding for the desired trait, other genes are added.  OtheSome of these genes promote the growth of only those plant cells that have successfully incorporated the inserted DNA. For example, providing the transformed cells with resistance to a normally toxic antibiotic that is added to the growth medium.r genes (“promoters”) may be added to control the functioning of the trait gene by directing when and where in the transformed plant it will operate.

 

 The analysis of which would be :

  • Some of these genes promote the growth of only those plant cells that have successfully incorporated the inserted DNA. For example, providing the transformed cells with resistance to a normally toxic antibiotic that is added to the growth medium.

 

 

 

From the sentence above, we can take conclusion that:

-          Some of these genes promote the growth of only those plant cells that have successfully incorporated the inserted DNA.

-          providing the transformed cells with resistance to a normally toxic antibiotic that is added to the growth medium.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CHAPTER IX

ABOVE THE CLAUSE:

EXPLANATION

 

In scientific writings word like “that is to say”, “in other words”, and “this mean” are used to show a relationshipbof explanation between two clauses.

Example in paragraph 12:

For example, the plant hormone ethylene is associated with accelerated ripening, as well as leaf and flower deterioration, in fruits that are injured or harvested. This mean insert genes that interfere with a plant’s ability to synthesize or respond to ethylene, thereby extending postharvest quality for many fresh products, including tomatoes, lettuce, and cut flowers. Scientists are also using gene insertion to improve a plant’s nutritional value and color.

 

The analysis of which would be :

  • For example, the plant hormone ethylene is associated with accelerated ripening, as well as leaf and flower deterioration, in fruits that are injured or harvested. This mean insert genes that interfere with a plant’s ability to synthesize or respond to ethylene, thereby extending postharvest quality for many fresh products, including tomatoes, lettuce, and cut flowers.

 

 

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