Inheritance Patterns- The Study of Genetics
- Define Genetics- The study of of heredity and variation. Heredity describes the passing of traits from the parents to their offspring.
- Genotype Vs. Phenotype- A genotype expresses what specific trait an organism has. While the phenotype shows what physical characteristics a certain organism posses.
- Cross Breeding- Many people cross breed when it comes to dogs when looking for a specific phenotype such as breeding two brown cats while expecting the offspring to be more brown cats (assuming they are pure bread). This is called a monohybrid cross.
- If someone were to breed an organism for traits such as intelligence , someone good at sports , or with a nice personality it would be called dihybrid breeding.
- Mendel's Principle of Dominance- While cross breeding may seem like a good idea, but Mendel's Principle of Dominance tells us that there still hidden recessive traits so the intelligent offspring you were hoping for is not guaranteed.
Genes, Genotypes, and Intermediate Patterns of Inheritance.
Some traits that are given to offspring are not all exactly one phenotype. Without complete dominance, many phenotypes are blended together to express multiple colors. An example of this would be flowers. When having a red flower and a white flower and their traits are both dominant which make a pink flower. Another example of incomplete dominance would be the color range that shows within dogs.
Another way traits can show an impact of dominance would be codominance. Codominance When looking at someone or something with codominance it is very easy to realize what it is. It is when two genes are dominant and cause a spark difference in coloration. An example would be a disorder called vitiligo. This is when the pigment within one’s skin is are destroyed. However, coloration is not the only way codominance shows within something. Disease shows codominance as well. Sickle cell disease is an example that can used to show codominance. Sickle cell doesn’t allow the the normal amount of oxygen to be carried in the blood stream. This disease along with being a sign of dominance in the person's genes it is also seen as a mutation.
While incomplete dominance and codominance are normally thought of to be the same thing, codominance and incomplete dominance not the same thing. In short, incomplete dominance is the blending of two traits and codominance is the contrast between two traits.
- Autosomal Inheritance Patterns
- sex chromosomes is the 23rd chromosome that determines the sex of an infant.
- Autosomes are the first 22 chromosomes in humans. As said earlier, if someone has a trait the does not mean that the offspring will receive the same trait. This means that the offspring will be a carrier of the specific genotype, which means that the recessive trait will show in different offspring in the long run. An autosomal recessive trait is almost the same but it contains disorders and diseases. For example if a person has dawn syndrome and the person's offspring has it only present in one copy of the allele then it would be considered recessive, therefore they would not have it.
- Autosomal Inheritance Patterns:
- Organism’s genome is located on the chromosomes
- Your genome is found within your chromosomes, and your sex is determined there, the pair
- Chromosomes come from your mother and father the human has 46 chromosomes (23 from your mother and 23 from your father.)
- One out of the 23 pairs of the chromosomes is the sex then the other 22 pairs are autosomes.
- Certain genetic diseases and sicknesses can be passed through autosomes due to your parents carrying them and passing them to you.
- Though you are not affected by the genetic disorder, you may be carrying it as a recessive trait that you could possible
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