BIOLOGY

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17.10.01

Konrad Lorenz
Compiled by Bethinee Snyder

VladislavVelkovski

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Zorana Sokolovska I-3 
High School’’ Kiril Pejcinovic’’   TETOVO

Konrad Lorenz
Konrad Lorenz was born on November 7, 1903 in Austria. As a little boy, he loved animals and collected a variety of them. He had fish, dogs, monkeys, insects, ducks, and geese. His interest in animal behavior was intense. A neighbor gave him a duckling and he noticed that it transferred it's response to him, discovering imprinting as a young child. When he was 10 years old, Lorenz discovered evolution by reading a book by Wilhelm Bolsche. He saw a picture of an extract Archaeopteryx ( reptile) and began to understand the relationship between an earthworm and insects. Evolution gave him insight. If reptiles could become birds, annelid worms could develop into insects. As an adult, he held doctorates in medicine, zoology, and psychology and became one of Austria's most famous scientists.
Initially, he wanted to become a paleontologist, although he was interested in evolution and wanted to study zoology and paleontology. However, he obeyed his father and went to medical school. He studied medicine at Vienna, became a professor at the Albertus University in Konigberg, and went on to direct the Institute of Comparative Ethology at Altenberg, where he created a comparative ethology department in the Max Planck Institute. He co-directed the program in 1954. He is considered the founder of ethology, who has given to the world a deeper insight of behavioral patterns in animals.
In 1966, he wrote On Aggression in which he argued that animal aggressive behavior is motivated by survival, while humans aggressive behavior may be channeled or modified. His other books include King Solomon's Ring (1949), Man Meets Dog (1950), The Eight Deadly Sins of Civilized Humanity, and The Decay of the Humane. In 1973 he won a Nobel Prize (shared with Karl Von Frisch & Niko Tinbergen) for his studies of human and animal behavior (photo on left). This was the first such prize to be awarded to behavioral scientists and was shared by the founders of the field of ethology. Konrad Lorenz was 85 years old whan he died in 1989.

1903- Lorenz was born in Austria
1941- Recruited into German army as a medical man
1942- Lorenz was sent to the front near Wilebsk
2 months later- Lorenz taken prisoner by Russians
1948- Lorenz back home to Austria
1949- Published King's Solomon Ring
1950- Published Man Meets Dog
1963- Published On Aggression
1973- Awarded the Nobel Prize. Established research station in Northern Alpine Valley
1989- Died.
Compiled by Bethinee Snyder

Clone, an organism, or group of organisms, derived from another organism by an asexual (nonsexual) reproductive process. The word clone has been applied to cells as well as to organisms, so a group of cells stemming from a single cell is also called a clone. Usually the members of a clone are identical in their inherited characteristics—that is, in their genes —except for any differences caused by mutation. Identical twins, for example, who originate from the division of a single fertilized egg, are members of a clone; whereas nonidentical twins, derived from two separate fertilized eggs, are not clones. Besides the organisms known as prokaryotes (the bacteria and cyanobacteria), a number of other simple organisms, such as most protozoans, many other algae, and some yeasts, also reproduce primarily by cloning, as do certain higher organisms like the dandelion or aspen tree.

 Through recent advances in genetic engineering, scientists can isolate an individual gene (or group of genes) from one organism and grow it in another organism belonging to a different species. The species chosen as a recipient is usually one that can reproduce asexually, such as a bacterium or yeast. Thus it is able to produce a clone of organisms, or cells, that all contain the same foreign gene or genes. Because bacteria, yeasts, and other cultured cells multiply rapidly, these methods make possible the production of many copies of a particular gene. The copies can then be isolated and used for study (for example, to investigate the chemical nature and structure of the gene) or for medical and commercial purposes (for example, to make large quantities of a useful gene product such as insulin, interferon, and growth hormone). This technique is called cloning because it uses clones of organisms or cells. It has great economic and medical potential and is the subject of active research.

 Identical-twin animals may be produced by cloning as well. An embryo in the early stage of development is removed from the uterus and split, then each separate part is placed in a surrogate uterus. Mammals such as mice and sheep have been produced by this method, which is generally called embryo splitting.

 Another development has been the discovery that a whole nucleus, containing an entire set of chromosomes, can be taken from a cell and injected into a fertilized egg whose own nucleus has been removed. The division of the egg brings about the division of the nucleus, and the descendant nuclei can, in turn, be injected into eggs. After several such transfers, the nuclei may be capable of directing the development of the eggs into complete new organisms genetically identical to the organism from which the original nucleus was taken. This cloning technique is in theory capable of producing large numbers of genetically identical individuals. Experiments using this technique have been successfully carried out with frogs and mice.

 Progress in cloning higher mammals beyond an early embryonic stage presents a much more formidable challenge. Genes in cells at the earliest stages of embryonic life carry the encoded knowledge that enables cells to develop into any part of the body. But skeptics theorized that once cells form into specific body components, they thereafter lose the capability to reconstruct the entire organism from the genetic contents of the nucleus.

 However, in July 1996, a team of Scottish scientists produced the first live birth of a healthy sheep cloned from an adult mammal. The team scraped skin cells from the udder of a donor sheep (sheep A) and these cells were temporarily starved of nutrients to halt cell development. An unfertilized egg was removed from a second sheep (sheep B) and its nuclear material was removed to eliminate genetic characteristics of the donor egg.  A skin cell from sheep A (containing a nucleus with genetic material) was fused with the unfertilized egg from sheep B. The egg, now with a full complement of genes, began dividing and was placed into the uterus of a surrogate mother (sheep C). The embryo developed normally and was delivered safely. Named Dolly, this healthy sheep was introduced to the world with much fanfare in February 1997.

 While Dolly has most of the genetic characteristics of sheep A, she is not a true clone. Not all of an animal’s genes are found in the cell’s nucleus. There are a few dozen genes that reside in the mitochondria outside the nucleus in the cell’s cytoplasm. In Dolly’s case, some of these genes were supplied by the donor egg of sheep B.

 The creation of Dolly represents a unique advance for cloning technology, but it inevitably intensified the debate about subjecting humans to cloning.  Rather than a prelude to human cloning, however, many scientists herald the achievement as the forerunner of a revolution in animal breeding that will allow the highest quality farm animals to be produced and will provide a cost-effective method of producing medicines for human use. Cloning may also be used to create genetically altered animals capable of providing major organs for surgical transplantation into human beings.