Science.8.13.B

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The student is expected to describe the function of genes within chromosomes in determining inherited traits of offspring; and
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Knowledge and Skills Statement

Organisms and environments. The student knows how cell functions support the health of an organism and how adaptation and variation relate to survival.

While DNA as the carrier of genetic information was not confirmed until 1944, research on the inheritance of traits had been taking place long before this. Key work was done by Gregor Mendel, a Moravian monk, who performed extensive experiments on pea plants, publishing his findings in 1866. Mendel followed certain binary traits through multiple cultivated generations, collected quantitative data, and subjected the data to statistical analysis. The analysis revealed that, for the traits Mendel examined, one form (allele) of the genetic factor (gene) is dominant, and one is recessive; each gamete contains only one allele of a gene; and alleles for separate traits are passed independently of each other. A gamete is a haploid cell that contains half the genetic material of a complete organism and can fuse with another gamete to form a zygote. Characteristics controlled by a single gene that has one dominant and one recessive allele are called Mendelian traits. Simple Mendelian inheritance patterns are relatively rare in nature and many of the Mendelian traits in humans cause disorders such as sickle cell anemia.

the process or product of the process by which the traits of a population change over time to better fit the environment in which the population lives

the basic unit of life; a collection of organic matter (cytoplasm) surrounded by a membrane, containing biomolecules such as DNA and proteins, and which has the ability to metabolize and replicate itself

any of the rod-shaped or threadlike DNA-containing structures of cellular organisms that contain all or most of the genes of the organism; located in the nucleus of eukaryotes and are usually ring-shaped in prokaryotes

segment of DNA that encodes for specific and complete proteins

specific variation in the characteristics of organisms received from a parent or ancestor by genetic transmission
 

the product of sexual or asexual reproduction

Research

Finnerty, Valerie Raunig. “Learning Genetics with Paper Pets.” Science Scope 29, no. 6 (2006): 18–23. http://www.jstor.org/stable/43181795

Summary: Students should understand basic gene inheritance by the end of the 8th grade. Scientific vocabulary is introduced to students before starting the activity. In this activity, students create paper pets with specific genetic traits to learn how traits are passed on to offspring. The students should note at least five inheritable genes of the parent pet. They will record the genotype on the back of their parent pet. Each parent pet will be matched with another parent in the class, producing paper offspring. Students use Punnett Squares to determine what traits their paper offspring could have. Groups should record the genotype and phenotype before creating their paper offspring.