Genetic Engineering Essay Research Paper Genetic EngineeringWe

Genetic Engineering Essay, Research Paper

Genetic Engineering

We find it mixed in our food on the shelves in the supermarket,

genetically engineered soybeans and maize. We find it growing in a plot

down the lane, test field release sites with genetically engineered

grape seed, sugar beet, wheat, potato, strawberries and more. There has

been no warning and no consultation.

It is variously known as genetic engineering, genetic modification or

genetic manipulation. All three terms mean the same thing, the

reshuffling of genes usually from one species to another. Existing

examples include; from fish to tomato or from human to pig. Genetic

engineering (GE) comes under the broad heading of biotechnology.

But how does it work. If you want to understand genetic engineering it

is best to start with some basic biology.

What is a cell. A cell is the smallest living unit, the basic

structural and functional unit of all living matter, whether that is a

plant, an animal or a fungus. Some organisms such as amoebae, bacteria,

some algae and fungi are single-celled – the entire organism is

contained in just one cell. Humans are quite different and are made up

of approximately 3,000,000,000,000 cells. Cells can take many shapes

depending on their function, but most commonly they will look like a

brick with rounded corners or an angular blob such as a building block.

Cells are stacked together to make up tissues, organs or structures.

In an organism, cells depend on each other to perform various functions

and tasks, some cells will produce enzymes, and others will store

sugars or fat. Different cells again will build the skeleton or be in

charge of communication like nerve cells others are there for defence,

such as white blood cells or stinging cells in jelly fish and plants.

In order to be a fully functional part of the whole, most cells have

got the same information and resources and the same basic equipment.

A cell belonging to higher organisms, such as a plant or animal, is

composed of a cell membrane enclosing the whole cell. Plant cells

have an additional cell wall for structural reinforcement. The

nucleus is the command centre of the cell. It contains all the vital

information needed by the cell or the whole organism to function, grow

and reproduce. This information is stored in the form of a genetic code

on the chromosomes, which are situated inside the nucleus.

Proteins are the basic building materials of a cell, made by the cell

itself. Looking at them in close-up they consist of a chain of amino

acids and small specific building blocks that easily link up. Though

the basic structure of proteins is linear, they are usually folded and

folded again into complex structures. Different proteins have different

functions. They can be transport molecules such as the oxygen binding

hemoglobin of the red blood cells, or they can be antibodies,

messengers, enzymes or hormones. Another group is the structural

proteins that form boundaries and provide movement, elasticity and the

ability to contract. Muscle fibres, for example, are mainly made of

proteins. Proteins are thus crucial in the formation of cells and in

giving cells the capacity to function properly.

Chromosomes means coloured bodies, as they can be seen under the light

microscope, using a particular colour of stain. They look like bundled

up knots and loops of a long thin thread. Chromosomes are the storage

place for all genetic, that is hereditary, information. This

information is written along the thin thread, called DNA. DNA is an

abbreviation for deoxyribonucleic acid, a specific acidic material that

can be found in the nucleus. The genetic information is written in the

form of a code, almost like a music tape. To ensure the thread and the

information are stable and safe, a twisted double stranded thread is

used, this is the famous double helix . When a cell multiplies it will

also copy all of the DNA and pass it on to the daughter cell.

The totality of the genetic information of an organism is called

genome. Human cells, for example, possess two sets of 23 different

chromosomes, one set from the mother and the other from the father. The

DNA of each human cell corresponds to 2 meters of DNA if it is

stretched out and it is thus crucial to organise the DNA in

chromosomes, so as to avoid knots, tangles and breakages. The length of

DNA contained in the human body is approximately 60,000,000,000

kilometres. This is equivalent to the distance to the moon and back

8000 times!

The information contained on the chromosomes in the DNA is written and

coded in such a way that it can be understood by almost all living

species on earth. It is thus termed the universal code of life. In this

coding system, cells need only four symbols, called nucleotides, to

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