November 27, 2011

November 27, 2011

November 27, 2011

This school year is flying past right now!  We just reached the midterm of second quarter and December is almost upon us.  You can look for the midterm reports in your mailboxes sometime at the end of this week or beginning of next, depending on the mail.

Events of the Past Week

Monday - The students ran a lab experiment called "The Limits of Cell Size," where they learned that the larger the surface area to volume ratio of a cell is, the quicker it is able to get nutrients in and waste out.  Cells have a larger surface area to volume ratio the smaller they are, which is why they need to divide after growing for a little while.  They also turned in their "Mitosis" lab and "Time for Mitosis" lab.  Homework was to complete the questions in the "Limits of Cell Size" lab.

Tuesday - The students first took a lab quiz over the cell size lab.  It was a 10 question quiz that we give to all of our freshman, no matter what level of biology they are in, because this is a lab we do at all levels of biology.  Most students did well on the short quiz.  The students then got back their two labs that they handed in the previous day, as well as the questions to the mitosis reading assignment from the previous week.

After all of the papers were passed back and everyone was done with the quiz, we reviewed for our quiz the next day by doing a pattern puzzle.  The students were given pictures of all of the stages of the cell cycle, as well as many statements about the events of the cell cycle to cut out and place in the proper order.  This took them a little while to complete, and they had to show me their completed work when they were done.  If they had made any mistakes, I pulled out the parts that were wrong and they had to go back and fix them to show me again until they had everything right.  Homework was to study for the quiz.

Wednesday - The students took their quiz over the cell cycle, which did include the five microscopes with one question at each microscope about cells in the various stages of the cell cycle.  This took the students most of the class period, so we did not do the cell energy assignment I had planned.  This is because I did not want them to have any homework over the Thanksgiving break, which I feel should be spent with family. 



Upcoming Events

Monday - After first going over the cell cycle quiz together, we will begin our next unit on cell energy.  This is one of the toughest units of the year because there will be a lot of new information which the students have not seen much of before, and some of the concepts are very high level.  The unit will begin on Monday with an introduction to enzymes, the molecules which speed up all of the chemical reactions in our bodies.  The students will be working in groups of 3 on a cooperative group project.  Each student will complete one part of a 3 part assignment on enzymes, and then be responsible for teaching the other members in his or her group the information in their part. 

Tuesday - Late Start Day - We will continue with the cooperative group project.  Students will complete the research on their part of the project, and then begin teaching each other.  Because of the shortened day, this will probably carry over into Wednesday.

Wednesday - Students will complete teaching their part of the project, and then have the opportunity to ask any questions that they might have about enzymes.  For homework, they will be looking at the lab that we will be running on Thursday and Friday with enzymes.

Thursday - This will be Day 1 of our enzyme lab.  Students will be working with an enzyme found in fresh pineapples called bromelain, which digests collagen.  Because of bromelain's function, gelatin, which is made of collagen, will not set up in the presence of fresh pineapple juice.  Students will be investigating which fruit juices contain bromelain, the effects of temperature on enzymes, and the effects of pH on enzymes during the course of this laboratory experiment.  If the enzyme bromelain is present and functioning, then the gelatin mixture they are working with will not solidify overnight in a refrigerator.  If the bromelain is not present or not functional, then the gelatin solution they will be working with will solidify overnight. 

One two member lab team will investigate whether or not bromelain is present in many different fruit juices, one two member team will investigate the effects of temperature on bromelain, and one two member team will investigate the effects of pH on bromelain.  Homework for each lab team will be to design a data table in which to record their results, and to begin writing up the procedure for their experiment.  The procedures will be written in the form of a flow chart.

Friday - Each two member team will observe their gelatin solutions to see whether or not they have solidified.  After recording their results, the teams will share their results with the other two member teams in their group.  They will then produce a procedure in flow chart form for each two member team, and answer 5 post-lab questions together as a big group.  Homework will be to study for a quiz on enzymes on Monday.

Graba Geek of the Week

This week's Geek of the Week award goes to Katie Schuelke, who worked very hard during the course of this unit and earned herself a perfect score on the lab quiz we took on Tuesday, and also earned a perfect score on the regular quiz on Wednesday.  That's the way to take yourself into Thanksgiving break!

November 20, 2011

November 20, 2011

November 20, 2011

As many of us are getting ready to enjoy a Thanksgiving meal on Thursday, make sure to pause and take time to be thankful for the family and friends we have in our lives. 

Events of the Past Week

Monday - NO SCHOOL - Teacher Institute Day

Tuesday - Periods were shortened to 37 minutes due to our late start meetings in the morning.  During our late start time we were examining our grading practices and philosophies, which made for interesting discussions and reflections. 

In class, I lectured to the students about the concept of chromosomes, chromatids, and chromatin, as well as the first stages of the cell cycle.

Wednesday - I was out of school on Wednesday, so the students did a reading on the cell cycle from a booklet put out by the National Institutes of Health.  There were questions associated with it, which they completed in class.  Homework was a coloring worksheet on the cell cycle.  I find that colored diagrams make are a much better study aid than black and white diagrams because all of the parts stand out a little bit better.

Thursday - The students finished taking lecture notes on the cell cycle.  When we were done with our discussion, the students then began a lab looking for cells in the various stages of the cell cycle under the microscope.  We were looking at prepared slides of the tip of an onion root to find cells in various stages of their life cycle.  Each lab team had to show me each stage as they found them so I knew that they had correctly identified all of the different stages of the cell cycle. 

Friday - We finished identifying cells under the microscope, and then moved on to a lab where students were determining how long cells spend in each stage of the cell cycle.  The big ideas the students should learn from this lab are:  cancer cells go through their life cycle much quicker than normal cells, interphase is the longest stage of the cell cycle, and prophase is the longest stage of mitosis.  Homework was to complete the questions in the two labs that we completed on Thursday and Friday.

Upcoming Events

Monday - Due to my absence on Wednesday of last week, we did not run the lab that we were going to do to learn about the importance of the surface area to volume ratio of a cell.  That lab will instead be run Monday.  Homework will be to complete the lab question for homework.

Tuesday - We will be spending some time reviewing the stages of the cell cycle on Tuesday, and I will be sharing with the students how cancer has impacted my life.  I will invite anyone who would like to share to also do so after I have shared my story.

Wednesday - The students will take their quiz on the cell cycle that will consist of 20 multiple choice questions and five microscopes set up around the room.  They will get 1 minute at each microscope to look at and identify cells in the different stages of the cell cycle.  There is a pointer in the microscope that I will have pointing directly at one specific cell for them to identify.  On the microscope portion of the quiz, they may also be asked questions such as, "Name two events that take place during this stage of the cell cycle."

After the quiz, the students will be given a packet where they will investigate a molecule called Adenosine Triphosphate (ATP) that provides our cells with the energy they need to work.

Thursday - NO SCHOOL - EAT LOTS!


Interesting Tidbits

For those of you looking for opportunities for your children to get involved in science outside of the classroom, I found this opportunity:  It is called the Dupont Challenge.  The idea is that students pick a topic in science that interests them, and write about it in an essay of no more than 1,000 words.  The winners of the competition can earn:
  • $5,000 U.S. Savings Bond

  • Expenses-paid trip to Kennedy Space Center and Walt Disney World® Resort with a parent

  • Subscription to Britannica Pathways: Science for entire school

  • 26-volume Compton's by Britannica Encyclopedia

  • Full set of Britannica Mobile Apps

  • Britannica Ultimate Reference DVD

  • Graba Geek of the Week

    This week's geek of the week award goes to Max Jahns in my 5th period class.  During our lecture last week Max was really engaged and asked some excellent questions.  It's a lot of fun to teach students who have good questions and are thinking critically about the information they are presented.  That's one reason I enjoy teaching the accelerated students so much!  Have a great week and a Happy Thanksgiving!

    November 13, 2011

    November 13, 2011

    November 13, 2011

    We are reaching that time of year where it seems like there are as many days off of school as there are days in school!  Students have Monday off as we will be meeting with other science teachers from all of the schools in District 211, and then on Tuesday we will be meeting as biology teachers on our late start day to analyze data from our cell test that all accelerated biology teachers gave last week.

    Events of the Past Week

    Monday - We took the 10 question quiz on cell transport as planned.  Afterwards, students worked on the analysis questions to their egg lab, and then began work on a review packet on cells.  They also handed in the "Osmosis in a Plant Cell" lab from the previous Friday.  Homework was to complete the review sheet.

    Tuesday - I handed back the "Osmosis in a Plant Cell" lab to the students, as well as their egg lab analysis questions.  We took the time to discuss the results of those labs.  Then, the students got back their 10 question quizzes from the day before and were given time to ask me about them.  The next item on the agenda for the day was to go through the review packet and see if there were any questions on that.  After going through the review packet, we finally had time for our review activity with butcher paper on each lab table that has been described in previous posts.  Homework was to study for the test on Wednesday.

    Wednesday - Students took their test on cells on Wednesday.  There were 55 questions on the test, the 48 common assessment questions that all accelerated biology teachers gave, and then seven questions that related directly to the labs we did in class.  The other accelerated biology teachers also ended up giving those questions to their students after looking at what I had put together, so we all gave the same 55 question test.  We plan to take a look at the results from that test together on Tuesday.  There was no homework Wednesday night.

    Thursday - Students got a chance to see how they did on the test.  The majority of students received A's or B's on the test.  The toughest portion of the test was definitely the portion on cell transport (diffusion, osmosis, active transport, etc.).  When we were done with this, the students began a reading on cancer that I located on the American Cancer Society website.  The students' homework is to finish the reading and take notes on it.  Only a class set of the reading was run off, so I linked the handout to my website ( on the accelerated biology "Worksheets and Presentations" page with a reminder of how far in the handout they have to read.  The idea behind having the students do this reading was to give them a reason to care about our next topic, cell division.  When cell division spirals out of control, cancer is the result.  Since it is estimated that one out of every two males and one out of every three females will be diagnosed with cancer at some point in their life, it is important to me that the students be educated about it.


    Upcoming Events


    Tuesday - LATE START DAY.  We will have shortened periods on Tuesday, so we will take a little bit of time to discuss the reading from the weekend (we will spend a little bit more time discussing cancer later in the unit), and I will lecture on the stages of the cell cycle, which includes the stages of mitosis. 

    Wednesday - The students will be doing a reading on the cell cycle and answering questions about it in class.  There will also be a coloring handout on the stages of the cell cycle for the students to complete.  Anything that is not finished in class will be homework.

    Thursday - We will do a lab where the students try to grasp the concept of surface area to volume ratio.  A cell needs a lot more surface area (cell membrane) than volume (cytoplasm and its contents) in order for nutrients to enter the cell quickly enough and waste to get out quickly enough for the cell to survive.  The lab will use cubes of agar of various sizes with sodium hydroxide and an acid/base indicator called bromothymol blue, which is blue in the presence of a base and yellow in the presence of an acid, inside of them.  The cubes will be placed into hydrochloric acid, and the amount of time it takes for the cubes to turn from blue to completely yellow will be recorded.  The students will see that the greater the surface area to volume ratio is, the faster the acid diffuses throughout the whole cube.  Homework will be to finish the lab questions.

    Friday - Class will start with a quick lab quiz to see what students learned from our agar cube lab.  We will look at slides of onion root tips, where cells are actively dividing as the root grows, to find cells in the various stages (interphase, prophase, metaphase, anaphase, and telophase) of the cell cycle.  Homework will be to finish the questions in the lab.

    Graba Geek of the Week

    This week's Geek of the Week award goes to Christopher Umeki.  Chris earned a perfect score on his test on cells, getting all 55 questions correct!  Way to go!  In addition, when a student asked when we'd learned that the smooth endoplasmic reticulum was responsible for detoxifying poisons (which was a question on the test), he was able to pull out his presentation and show the student the part of his presentation where he addressed that.  It always helps to be prepared! 

    Have a great week, everyone!

    November 6, 2011

    November 6th, 2011

    November 6th, 2011

    We have a short week this week, and the students have a 4 day weekend followed by a late start on Tuesday.  Everyone should be well-rested by next week!

    Events of the Past Week

    Monday - To begin class, we took the mass of our eggs and measured the volume of liquid in our cups after the weekend.  They were then placed in distilled water and left to sit overnight. 

    We then went over our quiz from Friday.  After that was done, we began a lab looking at plant and animal cells.  We accomplished the task of looking at cheek cells during this class period.  The students should have been able to identify the cell membrane, cytoplasm, and nucleus in the cheek cell. 

    Tuesday - The class periods were all shortened this day due to it being a late start.  The students were able to look at onion cells stained with iodine during the class period, and should have identified the cell wall, cytoplasm, nucleus, and nucleolus.  This was done after taking the mass of our eggs, measuring the volume of liquid left in our cups, and placing the eggs in 75 mL of corn syrup.

    Wednesday - This was the 50th day of school, so no homework was allowed to be assigned, and no tests could be given on Thursday. We began class by taking the mass of our eggs, measuring the volume of liquid in our cups, and throwing everything away.  Since the lab questions could not be assigned to be due on Thursday, I let the students know that they would be due on Friday.

    After we were done cleaning up our lab, I began to lecture about the structure of the cell membrane, as well as the concepts of diffusion, osmosis, facilitated diffusion, hypertonic, isotonic, and hypotonic solutions.  In the past, the concepts of hypertonic, hypotonic, and isotonic have been confusing for my students (as well as for the students of other teachers).  If you can encourage your children to study those terms it will help them on their upcoming quiz and test.

    Thursday - I finished lecturing about the way materials move into and out of cells by introducing the concept of active transport.  When the students were done taking notes, we moved on to a worksheet that helped to review the concepts from the lecture.  Students were to finish that worksheet for homework, in addition to completing the egg lab questions.

    Friday - Due to the shortened periods and amount of time needed in each class period to complete our egg lab, the quiz that was originally scheduled for today was pushed back until Monday.  Instead, we did two labs investigating osmosis and diffusion.  The first lab experiment involved putting a solution of egg white (protein), glucose (monosaccharide), and starch (polysaccharide), into a semipermeable bag, and then putting the bag in a beaker of distilled water.  The purpose of this lab was to investigate what effect the size of a molecule has on its movement through a membrane.  Through testing the solution in the beaker for the presence of monosaccharides, proteins, and polysaccharides, the students learned that small particles like monosaccharides can pass through a membrane, while larger particles, like proteins and polysaccharides, are too big to fit through a membrane.

    While the students were letting their bags sit in the beaker of distilled water, they looked at two wet mounts I had set up at microscopes at my desk.  The students did not set up the slides themselves because 13 of the 15 microscopes in the classroom were in use for a lab practical that was set up for my seniors.  The freshmen observed purple onion cells that were soaked in deionized water on one slide, and purple onion cells that were soaked in salt water on the other slide.  Ask them to show you their drawings and explain what happened on each slide.  They should be able to use terms like:  plasmolysis, hyptonic, and hypertonic in describing what they observed.  For homework, the students were to complete the questions associated with the purple onion lab.  They will be given time on Monday to work on the questions associated with the semipermeable bag lab. 

    Upcoming Events

    Monday - Class will begin with a short, 10 question quiz on the topics that were covered in lecture and lab during the previous week.  Afterwards, students will be given time to work on finishing the questions from the semipermeable bag lab.  Finally, when they complete those questions, they will be given a review packet on the topic of cells.  Homework will be to finish the review packet.

    Tuesday - We will begin by going over the questions in the review packet together.  Then the students will do the review activity with the butcher paper on each lab table that I described in the previous post.  Homework will be to study for a test on Wednesday.

    Wednesday - The students will take a test of approximately 60 questions on cells.  The other accelerated biology teachers and I have a set of 48 questions that we will all be giving so that we can compare data on how our students are doing on several different topics within our unit.  Hopefully, this will lead to discussions of what each of us is doing that helps our students learn the material in this unit to find what approaches work best for students.  The other 10-12 questions will be specific to material done in our class.

    Thursday - We will take a good amount of class time on Thursday to review the results of our cell test.  Students will analyze which topics they did well on, and which they could have performed better on, and do test corrections on those questions that they missed.  Finally, students will be given a brief reading assignment for homework over the weekend.


    Graba Geek of the Week

    My geek of the week actually goes back to our organelle presentations.  Alexandra Baumgart's presentation was one of the best presentations I have seen a freshman give in 14 years of teaching.  She took the risk of singing her part of the presentation solo in front of her peers.  This was very brave.  Alexandra did an outstanding job of singing her part, the information was factually accurate, and everyone was paying attention to her.  Great job, Alexandra!  I would not have been brave enough to do something like that when I was in high school!