Weather: Gas Density

For the first lesson of Chapter 11, students worked with dry ice and watched a couple of teacher demonstrations involving dry ice.  To begin class, students quickly assembled into groups of four and transferred a small amount of dry ice (provided in a styrofoam cup) into a deflated plastic bag which they sealed closed.  Students measured and recorded the mass of the dry ice added to the bag (by subtracting the mass of the empty cup from the mass of the cup with dry ice).  Students then observed the plastic bag throughout the remainder of the class period.

In the interim, students hypothesized about what they might observe when water ice and dry ice were heated on a hot plate, and also what would happen when water and dry ice were added to liquid water or vegetable oil.  They then observed the outcomes and recorded their observations on the Lesson 56 Worksheet.  Students also recorded the definitions of sublimation and evaporation, both of which are included in the Lesson 56 PowerPoint.

Students also received back their graded Chapter 10 quizzes.  Notes from the short answer section are pictured below, along with calculations of how to measure the volume of carbon dioxide gas inflating the plastic bags from the lesson.  Students may replace their short answer scores from the quiz by substituting new numerical values for the problems and solving the problems with the new numbers.

Weather: Unit Conversion & Significant Figures

With the HHS teachers out of the classroom for a Professional Development meeting on Thursday, students worked independently in small groups on an activity called Can You Lift It? The activity called for students to measure and calculate the interior volume of the classroom and then use that volume, along with density values that needed to be researched, to calculate the mass of the room filled with the indicated materials.  The activity required students to successfully use dimensional analysis.

To help students better understand how to perform dimensional analysis calculations, the Dimensional Analysis section of Appendix A in the back of the textbook (pages A16-17) was offered as extra credit (+10EC).  Additionally, the Scientific Notation section (Appendix A, pages A14-16) was also offered.  Students are also encouraged to watch the Crash Course video below for additional instruction on both topics:

Central Dogma: Chromosome Project

Update: March 2

Today marks the final day of class time for working on this portion of the Chromosome Project.  After our entry task, students who have completed the project will be offered the opportunity to present their work to the class for feedback.  For those who finish early, please complete The New Genetics reading assignment (Chapter 1) from February 9.  When that assignment is complete, the next reading assignment is Chapter 4 from Inside the Cell (define vocabulary words in bold and answer the questions at the end of the chapter).  Notes from the entry task are shown below:

Update: March 1

A complete presentation will have the following sections:

  1. Information connecting Chromosome, DNA, Gene, Protein, and Trait (Disease/Condition)
  2. Information about Disease/Condition
  3. Researcher = Your Name
  4. Research connection between Gene and Disease/Condition
  5. How is the disease/condition inherited? Are the genetics known?
  6. Update references in APA format

Use the Citation Machine website to help you cite your sources using APA format.  Sources need to be referenced on the last slide of the Google Slides document you are working on.

Original Post: February 25

Welcome to the Chromosome Project!  Yesterday you had the opportunity to research one or more genes known to be involved in a genetic disease or condition of interest to you.  You then located the gene on a particular chromosome.

Now your work begins!  Your mission today is to learn as much as you can about the gene you identified yesterday.  Record your findings in the Daily Log located in Google Classroom.

To research your gene, visit the NCBI Human Genome Resources page and enter your gene name into the “Find a Gene” box on the left panel.  Be sure to select “homo sapiens” in the pull-down box.  When the search completes, click on your gene name (typically the first gene on the list) and browse through the entry.  There is a ton of information provided!  The length of the gene can be found by hovering your mouse over the top green line under the “genomic regions, transcripts, and products” and looking for the number after the word “length.”  The length of the amino acid sequence can be found by clicking on the word “protein” on the right hand side of the page under Related Information.  Browse the entries for the full-length protein and note the number of amino acids in the protein.  The full-length protein can be challenging to find: look for an entry that does not include words like truncatedisoformpredicted, synthetic construct, or unnamed protein product.

Another great website to visit to learn more about specific genes is GeneCards.org.  Just type your gene name into the “Explore a Gene” search box and appreciate the power of the Internet!  NCBI PubMed contains a huge database of scientific papers – search for your gene and see what articles are out there.

You can use all of this information to edit the Chromosome Project Template Slides also located in Google Classroom.  If time permits, continue researching the disease/condition you selected.  Your goal is to learn what you can about what the disease/condition is and how it is inherited.

Welcome to research!  Use your time well and challenge yourself to learn new things!

Weather: Chapter 10 Quiz

In preparation for the Chapter 10 Quiz, students worked together as a class to answer the Chapter 10 practice questions at the end of the chapter.  Pictures of their work written on the whiteboards are shown below:

Students may use one page of notes for the quiz.  After the quiz, students will prepare for tomorrow’s activity (they will have a substitute teacher) by writing a procedure for how to measure the interior volume of our classroom, taking into account the volume occupied by fixed structures.

Central Dogma: Structure and Function of Genes

With several students missing class today because of testing and a field trip, we practiced converting amino acid sequences to DNA sequences and then reviewed the DNA mutations introduced yesterday.  Students modeled frameshift mutations by inserting or deleting individual DNA bases into their initial DNA sequences and decoding the new amino acid sequences encoded for by the mutated DNA.

Several students observed the introduction of premature stop codons into their amino acid sequences.  We then looked at the structure of chromosomes, zooming in on a segment of chromosome 22 and then focusing further on a single gene.  Students sketched out the gene and then learned the following vocabulary terms:

  • Regulatory DNA sequences: DNA bases that control gene expression.  Not transcribed into mRNA.
  • mRNA: introns and exons transcribed from a DNA segment (a gene)
  • Introns: stretches of DNA transcribed into mRNA that are excised (removed) before the mRNA is translated to protein.  Also called “junk DNA” – but shouldn’t be!
  • Exons: segments of DNA transcribed into mRNA that are stitched together after intron excision for translation into protein

The white board pictures below show how precursor mRNA is processed to remove introns and stitch together exons to form the mature mRNA.

Previously, scientists believed one gene coded for one protein.  As our understanding of introns and exons improved, and as scientists developed improved methods for sequencing mRNA, scientists realized that one gene coding for one precursor mRNA could actually make many different (yet related) proteins.  For example, one mature mRNA might include all of the exons (after all introns are removed), while another mature mRNA might be missing one or more exons.  Called alternative splicing, this process allows a gene to code for more than one protein and helps explain the vast diversity of proteins found in the different cells that make up the human body.  Remember, all cells share the same DNA, but only some of that DNA is expressed by certain cells, and that expressed DNA (mRNA) can be spliced in various ways resulting in many different proteins.

As we transition toward our study of chromosomes, students will research disorders with a known genetic cause (start here).  Students will also have access to a variety of posters showing the molecular basis of health conditions they may also wish to study.  One they have identified a disorder, students will research genes known to associate with the condition.  Finally, they identify the number of the chromosome on which their gene resides.  The chromosome number they identify will be their assigned chromosome for the Chromosome Project.  Students will have a substitute teacher tomorrow who will instruct them to use the Chromebooks to visit the class website for details about the Project and instructions for how to begin.

Weather: Density, Temperature, and Fronts

In the final lesson of Chapter 10, students focused their learning of temperature and volume back on the concept of weather as it relates to warm and cold fronts and the formation of clouds.  We worked through the ChemCatalyst in the Lesson 55 PowerPoint and then watched a clip of Kenvin Delaney, Jimmy Fallon, and Lucy Liu experiment with matter of different densities:

Students then worked through the Lesson 55 Worksheet which calls for them to reference the Weather Variables worksheet from Lesson 49.  For homework, students were assigned textbook questions 1, 3, 4, and 5.

Central Dogma: Cystic Fibrosis Case Study

In today’s lesson, we used a case study about cystic fibrosis as the mechanism to:

  • review the stop codon;
  • connect the concepts of protein structure and function;
  • review how R groups differentiate amino acids;
  • review how R group interactions result in protein folding;
  • discuss “structure equals function”;
  • bring a human face to a genetic disease;
  • and help students recall the mechanism of genetic inheritance.

For the entry task, students were challenged to consider how genes begin and end.  We discussed how mRNA sequences always begin with AUG (which codes for methionine, and amino acid which may also occur elsewhere in a protein).  Students were then reminded of the three “stop codons” and we reviewed how those work to release a protein from the ribosome.  We reviewed the structure of amino acids, focusing on the 20 different R groups and how those R groups each have different properties.  The interactions between R groups determine protein shape, and shape determines protein function.  When the sequence changes, the shape changes, thus changing the function of a protein.  We then moved into the cystic fibrosis case study, first watching the video below and then working through the lesson PowerPoint.

Pictures from the white board today: