Genetics

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Genetics (from Ancient Greek γενετικός genetikos, “genitive” and that from γένεσις genesis, “origin”), a discipline of biology, is the science of heredity and variation in living organisms. The fact that living things inherit traits from their parents has been used since prehistoric times to improve crop plants and animals through selective breeding. However, the modern science of genetics, which seeks to understand the process of inheritance, only began with the work of Gregor Mendel in the mid-nineteenth century. Although he did not know the physical basis for heredity, Mendel observed that organisms inherit traits via discrete units of inheritance, which are now called genes.

Genes correspond to regions within DNA, a molecule composed of a chain of four different types of nucleotides—the sequence of these nucleotides is the genetic information organisms inherit. DNA naturally occurs in a double stranded form, with nucleotides on each strand complementary to each other. Each strand can act as a template for creating a new partner strand—this is the physical method for making copies of genes that can be inherited.

The sequence of nucleotides in a gene is translated by cells to produce a chain of amino acids, creating proteins—the order of amino acids in a protein corresponds to the order of nucleotides in the gene. This relationship between nucleotide sequence and amino acid sequence is known as the genetic code. The amino acids in a protein determine how it folds into a three-dimensional shape; this structure is, in turn, responsible for the protein's function. Proteins carry out almost all the functions needed for cells to live. A change to the DNA in a gene can change a protein's amino acids, changing its shape and function: this can have a dramatic effect in the cell and on the organism as a whole. Two additional factors that can change the shape of the protein are pH and temperature.

Although genetics plays a large role in the appearance and behavior of organisms, it is the combination of genetics with what an organism experiences that determines the ultimate outcome. For example, while genes play a role in determining an organism's size, the nutrition and other conditions it experiences after inception also have a large effect.

For more information about Genetics, read the full article at Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.


News tagged with genetic

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Supervolcano eruption -- in Sumatra -- deforested India 73,000 years ago

Supervolcano eruption -- in Sumatra -- deforested India 73,000 years ago

Space & Earth / Earth Sciences

created Nov 23, 2009 | popularity 4.5 / 5 (17) | comments 3

A new study provides "incontrovertible evidence" that the volcanic super-eruption of Toba on the island of Sumatra about 73,000 years ago deforested much of central India, some 3,000 miles from the epicenter, ...


Cells defend themselves from viruses, bacteria with armor of protein errors

Biology / Cell & Microbiology

created Nov 25, 2009 | popularity 5 / 5 (7) | comments 1

When cells are confronted with an invading virus or bacteria or exposed to an irritating chemical, they protect themselves by going off their DNA recipe and inserting the wrong amino acid into new proteins to defend them ...


Opposites attract: Monkeys choose mating partners with different genes

Biology / Evolution

created Nov 24, 2009 | popularity 5 / 5 (1) | comments 0

The world's largest species of monkey 'chooses' mates with genes that are different from their own to guarantee healthy and strong offspring, according to a new research study.


New Switchgrass Germplasm Collected in Florida

New Switchgrass Germplasm Collected in Florida

Biology / Ecology

created Nov 26, 2009 | popularity not rated yet | comments 0

(PhysOrg.com) -- Agricultural Research Service (ARS) scientists and cooperators have collected 46 new populations of switchgrass in Florida, adding valuable new accessions to the germplasm collection of this ...


First 'genetic map' of Han Chinese may aid search for disease susceptibility genes

Medicine & Health / Genetics

created Nov 25, 2009 | popularity not rated yet | comments 0

The first genetic historical map of the Han Chinese, the largest ethnic population in the world, as they migrated from south to north over evolutionary time. was published online today by the American Journal of Human Ge ...


Discovery leads to effective treatment of painful skin condition

Medicine & Health / Diseases

created Nov 24, 2009 | popularity not rated yet | comments 0

Researchers at Huntsman Cancer Institute, in collaboration with a worldwide group of physicians and scientists, have discovered a remarkable treatment for a rare, yet debilitating, skin condition.


Against expectations, genetic variation does not alter asthma treatment response

Medicine & Health / Diseases

created Nov 24, 2009 | popularity not rated yet | comments 0

(PhysOrg.com) -- Studies have suggested that asthma patients with a specific genetic variation might not respond as well to certain treatments as those with a different variation. But a new study in this week's edition of ...


Beer Here

Biology / Other

created Nov 25, 2009 | popularity 4 / 5 (1) | comments 0

(PhysOrg.com) -- Drinking beer is a simple act, but making beer is not. It starts out with genetics and tens of thousands of barley varieties and ends with a clear ambrosia that belies the time, effort and technology that ...


It's a gas: New discovery may lead to heartier, high-yielding plants

Biology / Biotechnology

created Nov 23, 2009 | popularity 3.7 / 5 (3) | comments 0

In a research report published in the November 2009 issue of the journal Genetics, scientists show how a family of genes (1-aminocyclopropane-1-carboxylate synthase, or ACS genes) are responsible for production of ethyle ...


Racial disparity in colon cancer survival not easily explained, researchers say (w/ Video)

Medicine & Health / Cancer

created Nov 23, 2009 | popularity not rated yet | comments 1

A new study by University of Alabama at Birmingham (UAB) researchers shows that body-mass index (BMI) and co-existing medical conditions (co-morbidity) do not explain the decreased survival observed among African-Americans ...