Introduction
Have you ever wondered why you have your eye color or why you resemble your parents? The answer lies in genetics. Genetics is the study of heredity, or how traits are passed down from generation to generation. In this article, we will be reviewing the Amoeba Sisters video recap on the introduction to heredity and providing the answer key for the accompanying worksheet.
What is Heredity?
Heredity is the passing down of traits from parents to offspring. These traits can be physical, such as eye color or height, or they can be behavioral, such as a tendency towards shyness or extroversion. Heredity is determined by genes, which are segments of DNA that contain information about specific traits.
Mendelian Genetics
The principles of heredity were first studied by Gregor Mendel, an Austrian monk who conducted experiments on pea plants. Mendel discovered that traits are inherited in predictable patterns and that some traits are dominant over others. This became known as Mendelian genetics.
Genotype vs Phenotype
In genetics, there are two important terms to know: genotype and phenotype. Genotype refers to the genetic makeup of an organism, while phenotype refers to the physical characteristics that result from that genetic makeup. For example, if an organism has the genotype for brown eyes, their phenotype will be brown eyes.
Punnett Squares
Punnett squares are a tool used to predict the probability of offspring inheriting certain traits. They are named after Reginald Punnett, who developed the concept in the early 20th century. Punnett squares are a grid that shows all possible combinations of alleles that can occur in offspring from two parents.
Incomplete Dominance
Incomplete dominance is when neither allele is dominant and the resulting phenotype is a blend of the two. For example, if a red flower and a white flower are crossed and their offspring have pink flowers, this is an example of incomplete dominance.
Co-Dominance
Co-dominance is when both alleles are expressed equally and the resulting phenotype shows both traits. For example, if a black chicken and a white chicken are crossed and their offspring have black and white feathers, this is an example of co-dominance.
Mutations
Mutations are changes in an organism’s DNA that can result in new traits. Mutations can be beneficial, harmful, or have no effect at all. Mutations can occur spontaneously or as a result of exposure to environmental factors such as radiation or chemicals.
Conclusion
The study of heredity is fascinating and has important implications in fields such as medicine and agriculture. Understanding how traits are passed down from generation to generation can help us predict and prevent genetic disorders, as well as develop new crops and livestock with desirable traits. We hope this article and the Amoeba Sisters video recap on heredity has helped you better understand this important topic.
