Congratulations to the students who received a Golden Ticket for completing their Biology Task! Students who submitted final drafts on or before last Friday (2/14) received grades. Students who did not submit a final draft remain eligible for a Silver Ticket. Tasks receiving a score below proficient are eligible for one additional final Golden Ticket review on or before Friday, February 28, after which only Silver Tickets will be issued. Remember, Seniors and Sophomores may only defend Tasks that receive a Golden Ticket. All students must receive either a Gold or Silver Ticket to receive credit for a class.
Because of the short week, students are working on their Heredity Projects. These short reports are due next Monday (February 24) and should be uploaded to Ms. H’s Dropbox. There is a Heredity Project folder in each class period. The Heredity Projects will supplement lessons next week on multi-trait Punnett Square analysis and the inheritance of traits through changes to DNA.
In Lesson 7, we learned about the Austrian monk Gregor Mendel and his pea plants. Mendel’s careful study of how pea plants inherit traits allowed him to predict the existence of genes (he called them “particles”) nearly 100 years before DNA was discovered! Students then practiced analyzing trait inheritance patterns using a Punnett Square worksheet.
Reminder: Students must upload the final draft of their Task to Ms. H’s Dropbox folder (the Final Draft folder in their class period folder) by midnight tomorrow (Friday, February 14). Students who upload the Task before the deadline and who receive a grade of Proficient or better will receive a Golden Ticket!
Today we had a lively discussion of the effects of nature and nurture on various traits. We realized that the information encoded in our genes might make us appear and think a certain way, and yet our environment also plays an important role in making us who we are. The discussion transitioned to Lesson 6: mitosis and meiosis. Our previous emphasis on DNA replication and the vocabulary associated with the project from Lesson 1, coupled with the videos of DNA replication from Lesson 2, all created the foundation for readily understanding cell division.
Picking up where we left off before Task Week, in Lesson 5 we reviewed key vocabulary related to the Central Dogma. Students received blank copies of the vocabulary worksheet and were provided with time in class to transcribe Central Dogma-related definitions. The remainder of the class period was spent working in small groups to discuss and debate whether specific traits are inherited through nature or nurture. The purpose of this lesson was to provide students with a link between proteins (encoded by genes within DNA) and phenotype (traits that are readily observed). Next, we will turn our attention to how traits are inherited: mitosis and meiosis.
Take a break from Task Week and read up on some recent research coming out of the University of Washington. Evan Eichler, a geneticist at the UW, thinks he may have discovered how new genes are born:
“About 8 million to 12 million years ago, the ancestor of great apes, including humans, underwent a dramatic genetic change. Small pieces of DNA replicated and spread across their resident chromosomes like dandelions across a lawn. But as these “dandelion seeds” dispersed, they carried some grass and daisy seeds — additional segments of DNA — along for the ride. This unusual pattern, repeated in different parts of the genome, is found only in great apes — bonobos, chimpanzees, gorillas and humans.” continue reading here…
We are taking a breather from our Genetics unit and once again turning our sights on completing the Task. Students are receiving focused attention all week as they use the laptops in class to complete their final drafts. Students are encouraged to share their work and the grading rubrics provided in class with an adult at home for feedback. As always, I am also available for feedback and students can email me drafts or upload them to Ms. H’s Dropbox account.