What About the Stages of Mitosis?
Posted: Monday, June 20th, 2016
by Peter A’Hearn
The stages of mitosis are really important.
I’m not being sarcastic. Every cell in your body (save those used to make babies) went through the stages of mitosis. And if the stages of mitosis didn’t work with great precision at coordinating the dance of the chromosomes, you would not be a very well functioning human being. So the stages of mitosis are very important.
As a starting biology teacher, I spent much time and energy making sure my students knew the phases of mitosis. I brought in straw hats and flannel shirts and had my students do a “Mitosis Square Dance.” We tried to identify the phases in onion cells under the microscope. I came up with mnemonics so stupid I can’t remember them.
Turns out neither could the students. They would perform abysmally the first time they were tested on them, and by the time the final rolled around, only my two or three who remembered EVERYTHING knew them. This got me thinking about if they really were important. I had been taught them, and the book devoted considerable pages to them, so they must be something the students needed to know. I re-read the standards (the 98 standards at the time) and couldn’t find the stages of mitosis.
I did find meiosis (the baby making type of cell division) in the high school standards:
HS Biology 2a Students know meiosis is an early step in sexual reproduction in which the pairs of chromosomes separate and segregate randomly during cell division to produce gametes containing one chromosome of each type.
This got me reflecting on why I was teaching it. I couldn’t think of anything students could actually DO with their knowledge of the phases of mitosis. What real world problem could they understand or solve? It might come up on Jeopardy someday. It might come up on a college test– if magically they could remember something three of four years out that they couldn’t remember for a week. And in that case, the stages of mitosis would have been re-taught anyway.
Maybe a former student when they get to grad school will become involved in medical research involving understanding of and manipulation of the stages of mitosis. It would be cool to think so! If they do, they will have plenty of time for detailed study and will learn them in the ways that expert knowledge is learned, through deep engagement and problem solving. It would pretty arrogant as a high school teacher to think my square dances and silly mnemonics had anything to do with it.
So… what does this have to do with the NGSS? One of the challenges of implementation is that teachers are having a hard time deciding what to cut out. There are things teachers have taught and have come to accept as important knowledge that are not in the NGSS. If a teacher is thinking about NGSS as something to pile on top of everything you already teach, then transitioning to NGSS might seem like an impossible goal. We need to make hard choices about what to cut out.
Many teachers want to transition to NGSS but, at the same time, have a hard time letting go of content they have been teaching. Examples are the periodic table in 5th grade, the gas laws in high school chemistry, and lots of content in biology– the parts of the cell, the details of each body system, classification, and oh yeah, the stages of mitosis.
Does that mean that these details have no place in NGSS? Is NGSS just about vague generalities?
No! Our teaching under NGSS should be anchored in specific real world questions or problems so as not to be vague. A teacher could start with the problem of a genetic disease caused by mistakes in mitosis. This is true of many cancers. Using this context, students would learn as many details as needed to understand the problem and model their understanding. It’s not hard to see how several performance expectations could be bundled in a unit that is centered around genetic diseases. They might include:
HS-LS3-1: Ask questions to clarify relationships about the role of DNA and chromosomes in coding the instructions for characteristic traits passed from parents to offspring.
HS-LS1-1: Construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.
HS-LS1-2: Develop and use a model to illustrate the hierarchical organization of interacting systems that provide specific functions within multicellular organisms.
And finally, the place where mitosis does occur in NGSS:
HS-LS1-4: Use a model to illustrate the role of cellular division (mitosis) and differentiation in producing and maintaining complex organisms.
The assessment boundary leaves the importance of the phases pretty clear:
Assessment Boundary: Assessment does not include specific gene control mechanisms or rote memorization of the steps of mitosis.
So in a unit like this, it would be clear that mitosis is very important. It helps understand where living things come from and how they develop. It can explain how genetic information is duplicated and how mistakes can be made that lead to both diversity and disorder. It also makes it clear that memorizing the details is not a productive use of time.
The transition to NGSS is an opportunity to reflect on what we teach: Is it deep? Does it help explain the real world? Will it result in lasting learning?
Posted: Tuesday, March 14th, 2017
The pre-publication version of the new California Science Curriculum Framework is now available for download. This publication incorporates all the edits that were approved by the State Board of Education in November 2016 and was many months in the making. Our sincere thanks to the dozens of CSTA members were involved in its development. Our appreciation is also extended to the California Department of Education, the State Board of Education, the Instructional Quality Commission, and the Science Curriculum Framework and Evaluation Criteria Committee and their staff for their hard work and dedication to produce this document and for their commitment to the public input process. To the many writers and contributors to the Framework CSTA thanks you for your many hours of work to produce a world-class document.
For tips on how to approach this document see our article from December 2016: California Has Adopted a New Science Curriculum Framework – Now What …? If you would like to learn more about the Framework, consider participating in one of the Framework Launch events (a.k.a. Rollout #4) scheduled throughout 2017.
The final publication version (formatted for printing) will be available in July 2017. This document will not be available in printed format, only electronically.
Posted: Monday, March 13th, 2017
The 2017 Award Season is now open! One of the benefits of being a CSTA member is your eligibility for awards as well as your eligibility to nominate someone for an award. CSTA offers several awards and members may nominate individuals and organizations for the Future Science Teacher Award, the prestigious Margaret Nicholson Distinguished Service Award, and the CSTA Distinguished Contributions Award (organizational award). May 9, 2017 is the deadline for nominations for these awards. CSTA believes that the importance of science education cannot be overstated. Given the essential presence of the sciences in understanding the past and planning for the future, science education remains, and will increasingly be one of the most important disciplines in education. CSTA is committed to recognizing and encouraging excellence in science teaching through the presentation of awards to science educators and organizations who have made outstanding contributions in science education in the state and who are poised to continue the momentum of providing high quality, relevant science education into the future. Learn More…
Posted: Monday, March 13th, 2017
CSTA is now accepting applications from regular, preservice, and retired members to serve on our volunteer committees! CSTA’s all-volunteer board of directors invites you to consider maximizing your member experience by volunteering for CSTA. CSTA committee service offers you the opportunity to share your expertise, learn a new skill, or do something you love to do but never have the opportunity to do in your regular day. CSTA committee volunteers do some pretty amazing things: Learn More…
Posted: Monday, March 13th, 2017
by Marian Murphy-Shaw
If you attended an NGSS Rollout phase 1-3 or CDE workshops at CSTA’s annual conference you may recall hearing from Chris Breazeale when he was working with the CDE. Chris has relocated professionally, with his passion for science education, and is now the Executive Director at the Explorit Science Center, a hands-on exploration museum featuring interactive STEM exhibits located at the beautiful Mace Ranch, 3141 5th St. in Davis, CA. Visitors can “think it, try it, and explorit” with a variety of displays that allow visitors to “do science.” To preview the museum, or schedule a classroom visit, see www.explorit.org. Learn More…
Posted: Monday, March 13th, 2017
by Joseph Calmer
Probably like you, NGSS has been at the forefront of many department meetings, lunch conversations, and solitary lesson planning sessions. Despite reading the original NRC Framework, the Ca Draft Frameworks, and many CSTA writings, I am still left with the question: “what does it actually mean for my classroom?”
I had an eye-opening experience that helped me with that question. It came out of a conversation that I had with a student teacher. It turns out that I’ve found the secret to learning how to teach with NGSS: I need to engage in dialogue about teaching with novice teachers. I’ve had the pleasure of teaching science in some capacity for 12 years. During that time pedagogy and student learning become sort of a “hidden curriculum.” It is difficult to plan a lesson for the hidden curriculum; the best way is to just have two or more professionals talk and see what emerges. I was surprised it took me so long to realize this epiphany. Learn More…