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The genetics of dog hair colour is much more complicated than most people might think. There are many different genes, each themselves with sometimes three or four alleles, whose combination leads to the hundreds if not thousands of different coat varieties seen in canids both domestic and wild. Many people tend to think of genetics as working in the traditional Mendelian fashion of basic dominance and recessiveness of genes controlled by a single allele (say A/a), but dog hair colour is one of many examples where the answer is not that simple. The introduction of more than two alleles whose dominance over one another varies leads to many more possible combinations of traits and is why the pattern, colour, length and curliness of dog hair varies so widely across the family Canidae. One gene that plays a key role in coat colour is the agouti gene that encodes for a signalling molecule which disrupts the pathway in fur melanocytes (specialized pigment-producing cells) that leads to eumelanin production, these being darker brown and black pigment molecules. As a result, dogs that express the aguoti gene at high levels instead produce lighter phaeomelanin pigments that result in yellow, gold and even red coat colours. It's still not that simple however because the agouti gene has four alleles (a, a^w ,a^t , a^y ) each leading to varying levels of expression and different patterns of light and dark colours seen across the Canidae family.

Protein being one of our major food groups in our health plate is also a very controversial topic when determining what is good or not good for the human body. There are different sources of protein such as meats, fish, nuts, beans/lentils, cheese and poultry. Red meat is said to be high in saturated fat and is classified as a Group 1 carcinogen by the World Health Organization. A carcinogen is a substance that has the ability to cause cancer in living tissue, meaning that humans should limit the amount of red meat eaten a week. Although these meats such as lamb, beef and pork are 'probable' causes of cancer, they dont indicate the risk of getting cancer. There are benefits however to eating lean red meat such as vitamin B12, zinc and iron. Red meat is not only classified as being a probable cause of cancer, but it is also a leading cause of heart disease. In the states, cardiovascular disease is the number one leading cause of death. Many Americans should consider limiting the amount of red meat they eat and substitute it with a variety of other protein dense and vitamin dense foods such as tofu, fish and beans/lentils. A variety of vegetables also have a high content of protein and fiber such as broccoli, cauliflower, spinach and brussel sprouts.

In 1995, Minnesota middle school students sampled frogs in a nearby pond and found that half of them were deformed, and it  was discovered soon after that this was a widespread occurrence. A total of 8 frog and toad species were affected by this. Approximately 0.2% of frogs found in the area were deformed from 1973 to 1993, and that percentage increased to 2.3% by 1996. The cause of this deformity was found to be a species of trematode, Ribeiroia ondatrae, which are flatworm parasites that cause deformities and sometimes death in frogs. Trematode larvae in frogs cause cysts. If the cysts are in a developing tissue, it can cause a deformity; for example, if the cysts are found in a tissue that is developing legs, the cysts can cause extra or truncated legs. The occurrence of deformities in the frogs in the area had increased due to runoff of Atrazine, an herbicide (which is banned in the European Union and other developed countries) which kills plants in a pond, causing them to decompose and ultimately cause eutrophication of the pond. This eutrophication of ponds led to more snails in which trematodes begin their lives. The trematodes then move from the snails into the frogs, causing the deformities.

Speciation is the second most important evolutionary process in birds that is responsible for evolution. It is more common in Aves classes (all birds) mainly because they can geographically isolated from their original population due to migration. Allopatry causes isolation, which can occur under certain conditions. Allopatry can cause species to migrate from one place to the other and it prevents gene flow between species. Since species are migrating there is no genetic interchange between them. Various geographic changes can cause species to isolate such as movement of continents, glaciers, formation of mountains and islands. Human activity such as agriculture and deforestation can also cause species to isolate.

The EGFR/KRAS pathway, commonly mutated in pancreatic adenocarcinoma, is a promising area of focus for targeted tumor treatment. A point mutation in codon 12 of the KRAS oncogene is nearly ubiquitious to all pancreatic adenocarcinomas. Targeted therapies would need to specifically focus on this mutation in the cancerous cells without damaging the growth pathway in normal, healthy cells. A possible therapy that may accomplish this goal includes a microRNA with a complementary sequence for the point mutation, which would allow it to bind to only cancerous cells. After binding, expression of the EGFR/KRAS pathway would be blocked by either degradation of the mRNA or by blocking translation through a ribosome. A challenge that remains is introducing this interfering RNA into cancerous cells. Liposomes may serve as useful areas for transport inside the cell after binding to cancer-specific antigens on the surface.

There are four main types of biomolecules: carbohydrates, proteins, lipids, and nucleic acids. These biomolecules make up the cells that make up organisms and are responsible for the mechanisms within the body. Carbohydrates are composed of carbons, hydrogens, and oxygens. Monosaccharides bond to form oligosaccharides that can be bound to cell surface proteins to aid in cell signaling. Proteins are made up of amino acids, which are composed of a central carbon bound to an amino group, a carboxyl group, and a variable "R" group. The R group can be nonpolar, polar without charge, negatively charged, or positively charged, and the polarity of the R group will influence how different amino acids interact intramolecularly or intermolecularly with other molecules. On the other hand, lipids are made up of mainly hydrocarbons and are therefore insoluble in water. The saturation of different lipids vary, affecting the solidity of the lipid at room temperature. Fully saturated lipids have carbons saturated with hydrogens, while unsaturated lipids have double bonds between carbons, resulting in less surrounding hydrogens. Lastly, nucleic acids are composed of nucleotides that consist of a sugar ring, a phosphate group, and a nitrogenous base. The most recognized nucleic acid is DNA, and in DNA, nucleotide phosphate groups and sugars form phosphodiester bonds that make up the sugar-phosphate backbone. The nitrogenous bases form hydrogen bonds across the two strands of DNA to form the DNA ladder.

It is surprising to see how many similarities fish have with all other vertebrates considering how different they physically appear to be. One of these similarities is their bony skeleton that also consists of a skull which is something that is found in both vertebrate and fish. Fish have been present for around four hundred million years as opposed to mammals who have been around for 200 million years. Although they have been around for drastically different times their similarities do start after conception. A piece of evidence of evolution can be found in an embryo. All animals start their earliest development the same way, as a single cell. A fish embryo and a human embryo look almost identical with one another. Small ridges can be found in both of embryos in fish they develop into gills and for humans they become the portion of the lower jaw as well as middle ear and voice box. To bridge the gap between land animals and water animals a Tiktaalikfossil can be examined. Although fish do not have necks they can be found in the Tiktaalik, although it is an extinct fish it had many features of a tetrapod. Including the bone ratio of one bone, two bones, little bones that is also found in humans which is why this animal helps fill the gap.

Tiktaalik is a genus of extinct lobe-finned fish. As Tiktaalik roseae is the only species classified under the genus, Tiktaalik can be called a monospecific genus. It lived about 375 million years ago, during the Late Devonian Period. Although Tiktaalik generally had the characteristics of a lobe-finned fish, it also shared some traits with tetrapods: it had gills, scales, and fins, but it also had a robust ribcage, primitive lungs, and a mobile neck. Tiktaalik is often referred to as a “transitional fossil” because it also had intermediate features, such as half-fish, half-tetrapod limbs and joints with functional wrist joints and radiating, fish-like fins instead of toes. It also had an ear region that was half-fish, half-tetrapod. While it is not an ancestor to any currently living animal, Tiktaalik is evidence of animals with intermediate forms that bridged the evolutionary gap between fish with fins and animals with arms and legs.

Spinacia oleracea is a hardy leafy annual of the amaranth family (Amaranthaceae), a commonly used vegetable in the world, commonly referred to as spinach. Deep within the cells of these spinach leaves lies chloroplasts, a type of organelle characterized by its two membranes and a high concentration of chlorophyll. They are structures by which photosynthesis, the process by which carbohydrates are made from carbon dioxide and water in the presence of chlorophyll, use energy captured from sunlight by chlorophyll. This results in the production of oxygen and energy-rich organic compounds. Chloroplasts contain thylakoids, flattened sacs. Light energy (sunlight) reaching the thylakoids excites the chlorophyll pigments, causing them to drive electrons and hydrogen from water to NADP+, an electron acceptor. The electrons enter the electron transport chain, resulting in the products of ATP and NADPH (converted from NADP+). These are then used in the light-independent reactions of photosynthesis, where carbon dioxide and water are used to make organic compounds.

Based on the article and Mayr’s definition of a species, it is correct to say that coyotes (Canis latrans), wolves (Canis lupus), and dogs (Canis lupus familiaris) are separate species. The article mentions that in the past, and today, that all three species had the ability to breed with one another, but in Mayr’s definition there is an emphasis on “interbreeding natural populations.” In his article Kays says the last recent account of wolf and coyote mating took place a hundred years ago and was due to low numbers of wolves in the Great Lakes area. This forced both species to interact. The same occurred between dogs and coyotes as coyotes began moving east but could not find others and instead bred with feral dogs. Kays states that while interbreeding can happen, they are usually exclusive within their own group.