To reinforce concepts introduced in the video yesterday but not covered in the reading assignment, we spent today learning and applying the vocabulary of inheritance.  We dusted off the cobwebs from student memories from middle school, reviewing the vocabulary words of:

• genotype: the genetic makeup of an organism
• phenotype: the physical appearance of an organism
• allele: one of two or more forms that a gene could take
• dominant allele: an allele that is always expressed when it is present (usually represented by a capital letter)
• recessive allele: an allele that is not expressed when the dominant allele is present (usually represented by a lower case letter)
• homozygous: having two alleles that are the same
• heterozygous: having two alleles that are different
• probability: the likelihood of an even

We then applied the vocabulary to an example Punnett Square about eye color inheritance patterns.  Students were provided with the following set of notes to reinforce concepts learned yesterday and provide context for our work today:

We then applied these concepts to a Single-Trait Punnett Square Gizmo in which students worked together in pairs to complete a work packet which included a review and application of the vocabulary learned thus far.

Students looking for additional practice are invited to complete the Punnett Square worksheet.

For day one of our two-day lesson on the structure and function of genes, students were tasked with modeling the four types of DNA mutations described in yesterday’s case study on cystic fibrosis.  Students were given a wild-type DNA sequence and then had to solve the RNA and resulting amino acid sequences (see Structure and Function of Genes – Day 1 Power Point).  After a review of the types of mutations, students then introduced each type of mutation into the DNA sequence, solving both the RNA and amino acid sequences and connecting the vocabulary with the actual process of mutating DNA in specific ways to effect a specific outcome on the amino acid sequence.

Update: January 19

For day 2 of this lesson, we took notes on the structure of genes, including a review of how chromosomes are found in the nucleus of cells, how chromosomes consist of DNA coiled around histone proteins, and how genes consist of regulatory regions, exons, and introns.  At the end of the lesson, we previewed single-trait Punnett Squares to prime students for next week.