7th Ch. 4 Genetics
Section 1 ~Mendel's Work~
In this section students will learn about the contributions of Gregor Mendel and how his discoveries and understanding of heredity lead to the foundation of genetics. Students will also be able to identify what controls the inheritance of traits in organisms by comparing dominant and recessive alleles.
~Take a Class Survey Lab~
Human traits are controlled by dominant and recessive alleles, causing many different combinations of traits among a group of people ie: widow's peak, cleft chin, dimples, etc.... Students will be presented with the problem "Are traits controlled by dominant alleles more common than traits controlled by recessive alleles?".
Students will observe 6 traits about themselves, then as a class we will look at the number of students with the recessive allele and the number of students with the dominant allele to see if there is a pattern in what type of allele is more common.
Section 2 ~Probability and Heredity~
In this section students will define probability and describe how it helps explain the results of genetic crosses. They will learn the difference between a genotype and a phenotype. Students will also study the pattern of codominance in the colors of chicken feathers. In this section students will complete a number of crosses through punnett squares to explore the probability of passing on traits through parents.
Section 3~The Cell and Inheritance~
In this section students will describe the role that chromosomes play in inheritance. We will look at the number of chromosomes in humans and other living things as well as the contributions of Walter Sutton and his studies of sex cells and chromosomes in grasshoppers. Students will identify the events that occur to the chromosomes in sex cells of living things during the process of meiosis. Finally, in section three students will explain the relationship between chromosomes and genes.
Section 4~The DNA Connection~
Throughout section four students will learn about the four nitrogen bases that make up DNA, they will explore how this pattern forms the genetic code in living things. Students will then create a 3-D paper model of DNA following a specific "coded" pattern. Lastly for the chapter we will look at the three different types of mutations that can occur within the translation process of DNA replication.
Chapter Project ~All In the Family~
This project will give students the opportunity to create a family of "paper pets" based on phenotypes and genotypes of their "parent pet". First, groups of four will create their own "parent paper pet" by rolling a die to determine the facial characteristics of their pet. Then groups will find a mate and construct Punnett Squares to determine the possible genetic outcomes for six offspring from the parents traits. Students will explore how traits are passed from parent to offspring and how it is possible to predict the outcomes of genetic crosses.
