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Peppered Moth Simulation Name:______________________________________________ Objective: Simulate changes in moth population due to pollution and predation, and observe how species can change over time. Introduction: Charles Darwin accumulated a tremendous collection of facts to support the theory of evolution by natural selection. One of his difficulties in demonstrating the theory, however, was the lack of an example of evolution over a short period of time, which could be observed as it was taking place in nature. Although Darwin was unaware of it, remarkable examples of evolution, which might have helped to persuade people of his theory, were in the countryside of his native England.

Kentucky Blues The story of an Appalachian malady, an inquisitive doctor, and a paradoxical cure. by Cathy Trost ©Science 82, November, 1982 Six generations after a French orphan named Martin Fugate settled on the banks of eastern 's Troublesome Creek with his redheaded American bride, his great-great-great great grandson was born in a modern hospital not far from where the creek still runs. The boy inherited his father's lankiness and his mother's slightly nasal way of speaking. What he got from Martin Fugate was dark blue skin. DNA . Genetics In the 150 years since Mendel's first experiments, geneticists have discovered that genetic traits usually don't follow simple inheritance patterns. Some traits, like human eye color and stature, are produced by the interplay of many sets of genes; these are known as "polygenic traits." Other traits show a phenomenon called intermediate expression, in which a heterozygous genotype will produce a phenotype that's different from homozygous dominant genotypes. In snapdragons, for example, a homozygous dominant genotype makes red flowers, homozygous recessive makes white flowers, and heterozygous individuals are pink. In addition, some genes have more than two different versions.

Acquired traits can be inherited via small RNAs Columbia University Medical Center (CUMC) researchers have found the first direct evidence that an acquired trait can be inherited without any DNA involvement. The findings suggest that Lamarck, whose theory of evolution was eclipsed by Darwin's, may not have been entirely wrong. The study is slated to appear in the Dec. 9 issue of Cell. "In our study, roundworms that developed resistance to a virus were able to pass along that immunity to their progeny for many consecutive generations," reported lead author Oded Rechavi, PhD, associate research scientist in biochemistry and molecular biophysics at CUMC. "The immunity was transferred in the form of small viral-silencing agents called viRNAs, working independently of the organism's genome."

Animated Blood Types Since Rh negative people may produce anti-Rh antibodies, Rh positive blood should not be given to an Rh negative recipient. Based upon the above table, Rh positive recipients can theoretically receive positive or negative blood, and Rh negative donors can theoretically give to Rh positive and Rh negative recipients. Therefore, the "universal donor" is O Negative, while the "universal recipient" is AB Positive. Anti-Rh (immune-type) antibodies can readily pass through the placental capillary membranes.

Color Blind Chart Pattern baldness in men is a sex-influenced trait. It is not an X-linked trait like color blindness and hemophilia. Baldness is an autosomal trait and is apparently influenced by sex hormones after people reach 30 years of age or older. Amazing! Scientists: Our DNA is Mutating As We Speak! We Are Developing 12 Strands! A microscopic image of human chromosomes. Little Alfie Clamp has an 'extra arm' on one of his, in what is believed to be a world first.His condition left Alfie unable to see until he was three months old and his muscles were so weak he could not roll over on his own. He still suffers serious digestive problems and needs a cocktail of drugs every day to help his body absorb vital nutrients. He also suffers fits which sparked by high temperatures and metabolic problems stop him from eating or drinking. Since he was born, Alfie has been rushed to hospital six times - including twice just last month - when he stopped breathing.

Cracking the Code of Life Cracking the Code of Life PBS Airdate: April 17, 2001 ROBERT KRULWICH: When I look at this—and these are the three billion chemical letters, instructions for a human being—my eyes glaze over. But when scientist Eric Lander looks at this he sees stories. ERIC LANDER (Whitehead Institute/MIT): The genome is a storybook that's been edited for a couple billion years. And you could take it to bed like A Thousand and One Arabian Nights, and read a different story in the genome every night. DNA from the Beginning -animated experiments DNA from the Beginning is organized around key concepts. The science behind each concept is explained by: animation, image gallery, video interviews, problem, biographies, and links. DNAftb blog: It's the season of hibernation, something I've always wished I could do.

Stem cell controversy The stem cell controversy is the ethical debate centered only with research involving the creation, usage, and destruction of human embryos. Most commonly, this controversy focuses on embryonic stem cells. Not all stem cell research involves the creation, usage and destruction of human embryos. For example, adult stem cells, amniotic stem cells and induced pluripotent stem cells do not involve creating, using or destroying human embryos and thus are minimally, if at all, controversial.