Some forms of RNA can copy themselves and can actually edit other RNAs by adding and deleting nucleotides. These experiments support another hypothesis that RNA, rather than DNA, functioned as life's first information storage system. According to this hypothesis, life based on RNA have started when RNA fragments began to copy and edit themselves and assemble proteins. ... Later, storing genetic information could have similarly been passed on to DNA. In this way, over thousands of years, RNA, DNA, and proteins could have evolved into the complex system that characterizes life today. ...

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All organisms have similarities in their DNA sequences, so insights gained by non-human genomes often lead to new knowledge about human biology. DNA Replication DNA replicates (duplicates) just before cell division. ... The enzyme, DNA polymerase, grasps a template strand exposed by helicase and moves along the strand to make a new DNA strand. ... After DNA strands open, DNA polymerase adds bases to the strand and DNA ligase joins the ends. ... Most of the DNA in the human genome does not seem to have any function and is referred to as "junk DNA." ...

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I)Darwin's Dilemma A)Darwin set sail on December 27, 1831 for a cruise around the world 1)He was well educated and had a strong interest in natural history 2)He also had keen powers of observation and an analytical mind 3)Each place he went he collected animal and plant specimens to his collection (a)He examined his specimens and filled notebooks with his observations B)Throughout the voyage he witnessed countless wonders of nature 1)He demanded explanations for these wonders II)The Diversity of Life A)When Darwin visited tropical South America he saw countless species 1)In one ...

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How can the many similarities and differences among plants and animals be explained? ... -oOo- Studies state that difference from the last generation would be a product of mutations. It would be very possible that the evolution was caused by some changes in the DNA pattern. ... -oOo- Comparisons of blood proteins and the DNA and the RNA of the African apes with those of the human beings indicate that the line leading to modern people did not split off from the chimpanzee and the apes until comparatively late in evolution. ... -oOo- DNA extractions were done on both species the humans to...

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Important Facts the smallest unit of life is the cell instructions for development are contained in DNA collectively, all of the chemical processes in a cell are called metabolism producers often obtain energy from the sun homeostasis refers to the ability to maintain a constant internal environment cells in domains archaea and eubacteria lack nucleii plants are multicellular producers an educated guess might be called a hypothesis science is based on evidence philosophy is not a step in the scientific method an atom is the smallest unit of substance that retains the properties of the subst...

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The reason for such ambiguity is that we currently do not have the DNA sequencing data that is need to correctly categorize these animals with their proper species. ... This gene is one of the most often used as a DNA barcode to identify animal species. COX1 gene sequence has a mutation rate that is fast enough to distinguish closely related species and also because it sequences is conserved among conspecifics. 16S ribosomal RNA is another gene that is a component of the 30S and is used in reconstructing phylogenies.16S is used for generating phylogenies because of its slow rates of evolution ...

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