1a) Where are the oldest rocks found on Earth?
The oldest found whole rocks were found in the Nuvvuagittuq greenstone belt in northern Quebec along the east shore of the Hudson Bay. Samples taken from this site indicate an age of 3.8 to 4.28 billion years old, and were confirmed by measuring small variations in isotopic compositions of neodymium and samarium in the rocks.
Older grains of minerals, called zircons, have also been found in Western Australia, with ages of 4.36 billion years.
National Science Foundation (NSF) News – Oldest Known Rock on Earth Discovered: https://www.nsf.gov/news/news_summ.jsp?cntn_id=112299
1b) Are there other types of radiometric dating other than uranium to lead?
There are many types of radiometric dating, such as radiocarbon dating which is based on the radioactive decay of 14C in organic materials, with an accuracy topping out at less than 70,000 years. Similar methods measure the decay of Potassium-40 to Argon-40, Thorium-232 to Lead-208, Samarium-147 to Neodymium-143, and others.
Another way to date materials is by measuring the accumulation of electrons, dislodged by radiation, that have become trapped in imperfections in the crystal structure of the material being measured. Examples of this type of dating are Luminescence and electron spin resonance.
Nature – Dating Rocks and Fossils Using Geologic Methods:
http://www.nature.com/scitable/knowledge/library/dating-rocks-and-fossils-using-geologic-methods-107924044
2a) Have other important transitional fossils have been found?
One set of transitional fossils details the evolution from reptiles to mammals. Dimetrodon lived between 280 million years ago (mya) and 265 mya, had a sail on its back which allowed for partial regula...
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...-resistant CCR5-Δ32 allele formed by a breakdown of the pathocenosis due to the historical Roman expansion?:
http://sharc.sums.ac.ir/icarusplus/export/sites/sharc/unpload/6.pdf
Evaluating plague and smallpox as historical selective pressures for the CCR5-Δ32 HIV-resistance allele: http://www.pnas.org/content/100/25/15276.long
Detection of the CCR5-Delta32 HIV resistance gene in Bronze Age skeletons:
http://www.ncbi.nlm.nih.gov/pubmed/15815693/
6b) What type of mutation lead to this allele?
The CCR5-Δ32 gene is the name of the allele discussed in the video, as eluded to by its name it resulted from a frameshift mutation that occurred in the CCR5 gene resulting in the deletion of 32 base pairs (Δ32).
THURJ | Engineering recombinase enzymes to emulate the CCR5-Δ32 mutation conferring resistance to HIV-1 infection: http://thurj.org/research/2011/02/1238/
Sedimentary rock from the older Silurian Period is further from the river banks (Geological map of Victoria, 1973). Mudstone, inter-bedded shale and greywacke depositions indicate the Maribyrnong River may have previously taken a different shape, and younger sediments have replaced the older sediments in more recent geological periods.
When standing on top of the butte, the rock that makes up a majority of the area is quartzite. Quartzite is a metamorphic rock that forms when existing rock is exposed to extreme amounts of heat and pressure (4). The quartzite that is found on Kamiak Butte was formed sometime around 1.47 to 1.4 billion years ago during the Paleozoic period of the Precambrian era. Many of the metamorphic rocks have been fractured and decayed due to physical and chemical weathering, but because quartzite consists of one of the strongest minerals quartz...
If you know the half-life of k-40 than you can use the ratio of Ar-40: Kr-40 in a rock sample of a volcano you can find out the time the volcano erupted. If y0uu know this than it can help scientist learn more about the earths tectonic
More recently than Zeck’s work, Cesare et al. (1997), only divided the xenoliths into two main types: garnet-biotite-sillimanite and spinel-cordierite xenoliths. The quartz-cordierite rocks, distinguished by Zeck (1970), were interpreted as the products of interaction between garnet-biotite-sillimanite xenoliths and blebs of mafic magma and are not recognised. The xenoliths were observed to contain widespread occurrences of rhyolitic glass as...
Chondrites were made by the accretion of particles of dust present in the primitive Solar System which gave rise to asteroids over 4.55 billion years ago (SOURCE). These asteroid parent bodies of chondrites were small to medium sized asteroids that were never large enough to go through melting and planetary differentiation like Earth. Further evidence of age is shown through the abundance of non-volatile elements in chondrites which is similar to that found in the atmosphere of the Sun and other stars in our galaxy.[10] Even though chondritic asteroids never became hot enough to melt based upon internal temperatures, many of these asteroids did reach high enough temperatures to experience significant thermal metamorphism in the interior. T...
In the early 1800’s, a new discovery that left paleontologists in awe was the fossil finding of the immeasurable amount of species of reptiles, Ichthyosaurs. Greek for “fish lizards”, these fossils were found all over the world. Because these large aquatic reptiles migrated just as whales do today, paleontologists have had the amazing advantage of collecting fascinating bone fragments throughout the past 177 years. Ichthyosaurs swam the ocean life from about 245 million until about 90 million years ago- approximately the same time dinosaurs ruled the land. The earliest Ichthyosaur fossil findings were in parts of Canada, China, Japan, and possibly Thailand. Countless fossils came from coatings of limestone produced out of the ocean-floor ooze that was predominantly superior at preserving very well facts of the creatures it digested (Perkins 2).
While the carbon 14 method provided approximate dates for the stone rings it was no use
"Polymerase Chain Reaction (PCR) Fact Sheet." National Human Genome Research Institute. 10 Dec. 2007. National Institutes of Health. .
Scientists have long wanted to understand the environment and composition of the mantle. Teams of geologist have been trying for years to drill boreholes into the mantle. However, due to today’s technology and dwindling knowledge, as we get deeper and deeper into Earth, no one has come remotely close to getting there. Despite the failed attempts to collect material from the mantle, there are other ways that the mantle can be studied. One way is to study minerals that we can expect to find in the mantle such as wadsleyite. Wadsleyite was first discovered in the Peace River meteorite at Peace River, Alberta, Canada in 1966 and named after mineralogist Arthur David Wadsley. A phase transformation of the olivine, forsterite, wadsleyite is expected
In our genes, multiple different alleles determine whether one person will have a certain trait or not. Alleles are what make-up our genotypes and in this lab, we wanted to determine the genotypes of our class in the two loci: TAS2R38 and PV92. The TAS2R38 locus codes for a protein that involves the bitter taste of PTC; the gene determines whether or not a person will taste the PTC paper as very bitter or no taste at all. People with the “T” allele are tasters while those that are homozygous recessive (tt) are non-tasters. The taster locus can be found chromosome 7.3 The two different alleles present in the could be due to the effect of evolution and natural selection because the same can be found in chimps.4 The PV92 locus does not code for any protein but rather involves an Alu element that is 300-bp long. A person with the “+” allele would have the Alu element making that sequence longer while those with the “-“ allele don’t have the element and would have a shorter sequence. This locus can be found on chromosome 16.3 There are multiple Alu sequences found among primate genomes but there are human specific sequences such as the one found on the PV92 locus.1 In the experiment, student DNA was collected from cheek cells and PCR was used to target the loci and amplify the region of DNA. In the taster gene, after amplification, a restriction digest was performed to differentiate between the two alleles. The digest was able to show differentiation because those with the “T” allele would have two bands from gel electrophoresis and those with “t” will have one band because the restriction enzyme doesn’t cut it. For the PV92, we were able to distinguish between the alleles due to the added length of the Alu element. Those...
“The half-life of a radioisotope is the time required for half the atoms in a given sample to undergo radioactive decay; for any particular radioisotope, the half-life is independent of the initial amount of...
Radiocarbon dating is used to tell how old something is. When some normal carbon gets hit by the rays of the sun it turns into carbon 14. Plants absorb this radioactive carbon in the form of carbon dioxide. Animals receive this carbon from eating the plants. When the organism is dead it loses the carbon 14. Scientists can tell how old something is based on the amount of carbon 14 in a dead object. Carbon dating is accurate if the amount of carbon 14 in the atmosphere has remained the same throughout time. The second is if carbon 14 has always decayed at the same
The mineral diamond can be found in various places. Diamonds are found on planets such as earth, uranus, neptune, saturn, and jupiter. The atmospheres of these planets have the perfect temperature and air pressure conditions to host the carbon in form for the diamond. Diamonds must be in an area with very high temperatures and high pressure for the diamond minerals to be able to form. They need the high temperatures to allow them to become stable ad have a good foundation.
In this lab, eight unidentified mineral samples are the subject of observation and experimentation. The purpose of this lab is to identify the samples based on the observations and experimentation. This paper will identify each of the samples and briefly discuss each one.
...ary part in genotypes of potential interest that human geneticists breeders, as well as evolutionary geneticists are investigating. However, although we have the capability to unravel experiments that the founders of quantitative genetics would have never imagined, but their basic, un-computational machinery that they developed is most easily adaptable to the latest analyses that will be needed. We are far from ‘letting-go’ molecular biologists from the mathematical techniques/systems, because this age in respect to genomics has been forced into accepting gratitude due to the major importance of quantitative methods as opposed to the new molecular genetics. As geneticists tend to map molecular variation as well as genomic data, quantitative genetics will be moving to the front position because of its relevance in this age of rapid advancement in molecular genetics.