Each Cell Has a Job

Lesson Plan - Get It!

Audio:

Stem cells are a very controversial topic in the media today, and while we won't discuss the political aspect of the argument, there is a very important concept rooted in the biological development of stem cells.

Before moving on, if you missed or need to review the first lesson in the Cells Working Together series, find it in the right-hand sidebar under Related Lessons.

These important cells are able to differentiate into any type of cell in the human body. All of your cells originated from stem cells — brain cells, blood cells, skin cells, muscle cells, and nerve cells all came from a single origin! That is incredible!

• So, how are these cells able to take on such different functions in the body?

Watch What are STEM CELLS? And What Can they Do?, from FreeMedEducation, to learn more:

• Can you believe that all of your cells came from a single stem cell?
• Why does a human need so many different kinds of cells?

It may be because we have very complex systems that require different kinds of processes. Humans aren't the only organisms with specialized cells; many eukaryotes have similar types of cells.

Take some time to discover some specialized cells in another organism.

• How do plants get nutrients and water from the roots to the leaves?

Specialized structures, called the xylem and phloem, move materials and water throughout the plant.

Observe the image:

^{Image by CNX OpenStax, via Wikimedia Commons, is licensed under the CC BY 4.0 license.}

• Can you see differences in cell structure?

These differences allow xylem and phloem to complete their job in the plant!

• Notice how the xylem are smaller structures?

Xylem is responsible for moving water, while phloem, the larger structure, moves nutrients for the plant.

• So, how do cells know what job to do?

Well, that is based on the process of differentiation, which is based heavily on environmental factors. During differentiation, environmental factors such as chemicals, temperature, and pH determine how cells develop into different shapes with different functions.

As you watch Cell Differentiation, from Patrick Haney, jot down the definition and contributing components that determine how cells differentiate:

Just think of all the environmental factors that influence a cell's journey.

You will look at structure and function more in depth in the Got It? section.