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FC: By: Carol V. and Katie K. | Heredity
1: Table Of Contents | What is Heredity? Gregor Mendel Vocabulary Punnett Squares How to use a Punnett square Facts Review Guide Citations | Page 1 Page 2 Page 3 & 4 Page 5 Page 6 Page 7 & 8 | Page 9 & 10 Page 11 & 12
2: What is Heredity? | Heredity is the passing of traits from parents to offspring (one generation to another) influenced by DNA. Through Heredity, variations by individuals can cause some species to evolve. Heredity happens in organisms and humans. Living things inherit traits from their parents through this process.
3: Gregor Mendel was born on July 22nd, 1822 in Czechoslovakia. During his childhood, he worked as a gardener and as he grew up, he attended the Olmutz Philosophical Institute. Mendel later was sent to the University of Vienna. He was inspired to study the variance of plants. | Between 1863 & 1866, Mendel tested around 28,000 pea plants. He looked at the stems of the pea plants and realized that some of the pea plants had the same traits as their parents. His experiments brought 2 generalizations that became as Mendel's law of heredity. He became know as the Father of Genetics. | Gregor Mendel | Father of genetics | Mendel's law of heredity: | 1st law: For each gene, there are 2 alleles, 1 from each parent the dominant allele will be expressed instead of the recessive allele. | 2nd law: During gamete formation, the distribution of each allele from a pair of chromosomes is entirely independent.
4: Vocabulary | Genotype: | The genetic makeup of a particular organism. Ex) Tt | Phenotype: | The physical appearance of a particular organism. Ex) Tall | Heterozygous: | Both alleles are unalike, also called a hybrid. Ex) Tt | Homozygous: | Both alleles are alike, also called a pure bred. Ex) TT or tt | * Alleles are an alternate form of a gene that represents a specific variation of a genetic trait *
5: Dominant: Recessive: | The letter that is capitalized, it masks the other allele if a dominant one is present. Ex) | T | t | The letter that is lowercase, it is hidden by dominant traits unless there isn't a dominant trait ( it is still derived by parents) Ex) T | t | Remember: | Each genotype, for example: Tt, there can only be 1 letter used like the letter T -uppercase and lowercase- when written. If it's written like Th, it's incorrect because there are 2 letters used, T and H.
6: Punnett Squares | Punnett squares is a diagram that is used to predict the outcome of a particular cross or breed. Reginald Punnett also experimented with pea plants and made the punnett square.
7: Let's say that you want to breed a heterozyous dominant yellow pea plant with a homologous recessive green pea plant. Since the yellow plant is dominant and heterozyous, the plant is written Yy. The green plant is written yy. Arrange the letters like above. | How to use a punnett square | Then you cross the alleles and it shows the possible combinations of how the offspring will turn out. Right above, 50% will be yellow and 50% will be green!
8: Facts: | * Each of your characteristics are a mix of 2 instructions, 1 from your mother's chromosomes and 1 from your father's chromosomes. | * Each characteristic is the work of 1 gene, either from the mother or father. -Dominant- | * The other gene (either form the mother or father) that isn't expressed doesn't vanish, it stays dormant in your chromosomes and it can possibly get passed down the generation. -Recessive-
9: * The recessive gene may be expressed when there's no competition, no dominant gene. Remember that the genes from both parents must both be recessive in order for the recessive gene to be expressed. | * It took Mendel 7 years to prove the laws of inheritance
10: Review Guide | Try this!
11: If there was a homozygous red flower that is dominant that bred with a purebred white flower that is recessive, what is the percent that the offspring will be red? | When Gregor Mendel studied the pea plants, what part of the pea plant did he look at? | What does heterozygous mean? | Is the following correct or incorrect: gH. Why?
12: Citations | "Gregor Mendel's Discoveries." | Think quest. | Oracle Foundation. Web. 16 May 2012. 13: "Gregor Mendel" | Gregor Mendel (1822-1884) | Web. 16 May 2012.
13: "Gregor Mendel" | Gregor Mendel (1822-1884) | Web. 16 May 2012.