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Genetics and the tree of life

Genetics and the tree of life
We traditionally think about the tree of life in terms of Kingdoms: plants, animals, fungi, bacteria, etc. Genetics has really revolutionized the way we think about the tree of life and, because our classifications should reflect ancestry (that is, who is more closely related to whom), it has actually called into question a lot of our traditional classifications. Most biologists split up life into three domains: Archaea, Bacteria, and Eucarya (the last of which includes animals, plants, fungi, etc.). The three domains of life. From Carl Zimmer's blog The Loom. Science writer Carl Zimmer has an interesting post on his blog about how the newest genetic data may even call this classification into question by adding a fourth domain. There’s a lot of debate about whether eukaryotes actually split off from within the archaea, or just branched off from a common ancestor. New research is looking at tons of genes from these sorts of organisms. References Wu, D., et al. (2011). Like this:

History of molecular evolution The history of molecular evolution starts in the early 20th century with "comparative biochemistry", but the field of molecular evolution came into its own in the 1960s and 1970s, following the rise of molecular biology. The advent of protein sequencing allowed molecular biologists to create phylogenies based on sequence comparison, and to use the differences between homologous sequences as a molecular clock to estimate the time since the last common ancestor. In the late 1960s, the neutral theory of molecular evolution provided a theoretical basis for the molecular clock, though both the clock and the neutral theory were controversial, since most evolutionary biologists held strongly to panselectionism, with natural selection as the only important cause of evolutionary change. After the 1970s, nucleic acid sequencing allowed molecular evolution to reach beyond proteins to highly conserved ribosomal RNA sequences, the foundation of a reconceptualization of the early history of life.

History of Life by Jesse Brunner on Prezi Biomedical science funding We support research into all aspects of biomedical science: from molecules and cells vital to life, through the spread of diseases or the vectors of disease across the globe, to clinical and public health research to improve the quality of healthcare. Research can be based in the laboratory, the clinic or the field, and may involve experimental or theoretical approaches. We do not just fund scientists - through our biomedical science grants we support undergraduate and doctoral students, clinicians, dentists and veterinarians. We fund the best researchers with the most innovative and exciting ideas in the form of personal and research support, collaborations and support for symposia, conferences and workshops. A significant proportion of our funding is devoted to support those working overseas. About biomedical science We support molecular, cellular and structural biology, as well as clinical, physiological, psychological, epidemiological and public health research. Our funding schemes :: Home The History of Life on Earth by Robert Patierno on Prezi thisviewoflife stand up for REAL science Critical analysis is at the heart of the scientific process. Scientists have been critically analyzing evolutionary theory for nearly 150 years. As it stands, the vast majority of scientists worldwide accept evolution as a "vital, well-supported, unifying principle of the biological sciences." A campaign is underway across the US to promote the "critical analysis" of evolution in public school science classrooms. This campaign can also be found under the guises of "teaching the strengths and weaknesses of evolution" or "teaching the controversy about evolution." Unfortunately, these phrases are being used as euphemisms for the notion that the scientific evidence supporting evolution and long-refuted "criticisms" of evolution should be treated equally. What is most notable about the recent campaign to promote "critical analysis" is that the theory of evolution has been singled out.

Cell Size and Scale Some cells are visible to the unaided eye The smallest objects that the unaided human eye can see are about 0.1 mm long. That means that under the right conditions, you might be able to see an ameoba proteus, a human egg, and a paramecium without using magnification. A magnifying glass can help you to see them more clearly, but they will still look tiny. Smaller cells are easily visible under a light microscope. It's even possible to make out structures within the cell, such as the nucleus, mitochondria and chloroplasts. To see anything smaller than 500 nm, you will need an electron microscope. Adenine The label on the nucleotide is not quite accurate. How can an X chromosome be nearly as big as the head of the sperm cell? No, this isn't a mistake. The X chromosome is shown here in a condensed state, as it would appear in a cell that's going through mitosis. A chromosome is made up of genetic material (one long piece of DNA) wrapped around structural support proteins (histones). Carbon