Stem cells are the foundation upon which our body grows. What do we really know about them? What are the concerns about stem cell research? Students should have some basic understanding about stem cells.
This lesson extends student thinking beyond the standard to understanding the concept of stem cells, cells that become any type of cells. The Performance Expectations are identified by (MS-LS3-1 - Use argument supported by evidence for how the body is a system of interacting subsystems composed of groups of cells.) Students are challenged to understand the concept of stem cells and understanding the difference between the facts and myths surrounding this controversial topic. (SP7 - Engaging in Argument from Evidence)
To take a look at the specific standard we are focusing on in this lesson, it is helpful to search NGSS Performance Expectations. You can use the form found here.
Grade Band/Level - Middle School
Practices - Engaging in Argument from Evidence
Disciplinary Cored Ideas - LS1A: Structure and Function
The resulting display below shows me the standard, LS1.A, that was used to develop the performance expectation MS-LS3-1.
This lesson about stem cells meets the standard by helping students understand how the connection between specialized cells -> tissues -> and organs begins with stem cell differentiation (LS1.A Structure and Function - in multicellular organisms, the body is a system of multiple interacting subsystems. These subsystems are groups of cells that work together to form tissues and organs the are specialized for particular body functions)
The chart also provides a wealth of additional information be me to consider as I develop student skills and understandings. Engaging in Argument from Evidence helps define the transition from K-5 to middle school. In this lesson students must critically examine the explanations about stem cells and associated myths. Using Systems and System Models, as a guide I can be sure students understand that stem cells are part of a much larger and more complex system. As we explore developing ideas in science it is also helpful to stress that scientist are guided by habits of mind such as intellectual honesty, tolerance of ambiguity, skepticism, and openness to new ideas.
To extend this lesson, it is helpful to consider the vertical articulation of the standard as well as the cross-curricular connections. Students will engage in writing arguments focused on discipline content in the lesson - Stem Cells or Cloning - You are the Expert!
Students in Action
I introduce today's lesson by briefly describing stem cells.
Scientists think that stem cells may change the future of medicine. What if your doctor could replace an organ or limb by making a new one with your own cells?
Stem cells are cells whose job has yet to be defined. Scientists researching stem cells can determine how healthy cells replace damaged cells. The more scientists discover about stem cells, the more questions they have about their potential for human health and repair.
The What are Stem Cells video provides a good overview of stem cells.
Today we will take a closer look at stem cells by searching for information on the Learn Genetics site developed by the University of Utah.
Your goal in completing this web quest is to be in a position to understand the conversation or news story about stem cells. You should understand the basic vocabulary used to discuss stem cells.
After researching the basics of both stem cells and cloning, you will pick one of the topics in which you will become an expert (Stem Cells or Cloning - You are the Expert). You will understand more than just the basics, you will be able to explain the topic to someone else.
What I like about this web quest is the variety of presentation strategies used to engage students. This video describes the different ways the students are engaged.
Let's take a close look at the types of stem cells.
Potent - is the Latin word meaning - to be able
As we break down the type of stem cells into the word parts, we see that scientific vocabulary can often be broken down into word part that help us quickly determine the definitions.
What happens during differentiation? Cells develop into a specialized type.
What are the potential benefits and concerns about stem cells? Damaged tissue can be repaired by activating stem cells, the best stem cells are embryonic stem cells, they have the most potential. Scientists are researching how other types of stem cells could be "programmed" to be like embryonic stem cells.