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The Study of Genetics

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What is Genetics?

  Go to fullsize imageGenetics is the passing of traits from parent to offspring. A monk named Gregor Mendel, realized how genetics works and is considered the "father" of genetics. Now, most scientists use a simple tool called a Punnett Square, to calculate the probablity of certain genetic traits to appear from the union of parental cells .  Punnett Squares help scientists estimate what traits the offspring will inherit from his/her parents.
  In genetics, the cells go through a process called Meiosis. Meiosis is different from Mitosis because the process involves the halving of the cells. DNA is passed to the offspring through chromosomes. The offspring gets half of it's DNA from it's mother, and half from it's father. All traits are inherited from common ancestors. For instance, birds might have inherited wings from pterodactyls. Many different animals are related because they share a common ancestor. A human also inherits traits from his or her ancestors.
     As time goes on, traits will continue to combine. That's why every human and animal is different. Each animal and plant contains a specific set of chromosomes in their body cell called the diploid or 2n number. For example, humans contain 23 pairs  which equal a diplod number of 46, the fruit fly contains 4 pairs thus a diplod number of 8. In contradiction to what you might think, new species do not form when different animals mate. Since different animals have a different number of chromosomes, they cannot have fertile offspring. For example, a bird and a cat cannot have offspring because they have a different amount of chromosomes.
     A new species forms when members of a species are separated from other members of a species. Birds from California will look different then birds from Florida because of different surroundings. One bird may need longer claws to survive, while the other bird only needs shorter nails. Since they do different things to adapt in their environment, they are now known as different species of the common bird family.  Go to fullsize image