Thursday, December 25, 2008

Human languages

Human languages are usually referred to as natural languages, and the science of studying them falls under the purview of linguistics. A common progression for natural languages is that they are considered to be first spoken, then written, and then an understanding and explanation of their grammar is attempted.

Languages live, die, move from place to place, and change with time. Any language that ceases to change or develop is categorized as a dead language. Conversely, any language that is in a continuous state of change is known as a living language or modern language.

Making a principled distinction between one language and another is usually impossible. For instance, there are a few dialects of German similar to some dialects of Dutch. The transition between languages within the same language family is sometimes gradual (see dialect continuum).

Some like to make parallels with biology, where it is not possible to make a well-defined distinction between one species and the next. In either case, the ultimate difficulty may stem from the interactions between languages and populations. (See Dialect or August Schleicher for a longer discussion.)

The concepts of Ausbausprache, Abstandsprache and Dachsprache are used to make finer distinctions about the degrees of difference between languages or dialects.

Monday, December 15, 2008

Genetics


Genetics (from Ancient Greek genetikos, “genitive” and that from 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 in a discrete manner—these basic units of inheritance are now called genes.
DNA, the molecular basis for inheritance. Each strand of DNA is a chain of nucleotides, matching each other in the center to form what look like rungs on a twisted ladder.

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 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.

Wednesday, December 03, 2008

Grain milk


Grain milk is a milk substitute made from fermented grain or from flour. Grain milk can be made from oats, spelt, rice, rye, einkorn wheat or quinoa.

Grain milk looks very similar to cow's milk. It has a lower protein content and a higher carbohydrate content than cow's milk. Just as cow's milk is often fortified with Vitamin D, which it naturally lacks, grain milks may have calcium and some vitamins (especially B12) added to them.

Grain milk is low in saturated fat and contains no lactose, which is beneficial for those who are lactose intolerant. Grain milk also lacks milk protein, making it suitable for vegans and people with milk allergies.

Flavored grain milk can come in plain, vanilla, chocolate or a variety of other flavors. Like unflavored grain milk, it is often available with added nutrients. There are also grain milk cream and desserts available.