Cell Specialization

Biological Hierarchy

Everyone begins as a single cell. Over time, that cell divides and multiples. At some point, cells begin working together to form tissues, tissues form organs, and organs form organ systems. A combination of organs systems makes up an organism. This system of organization is known as biological hierarchy. In this interactivity, learn about the biological hierarchy by investigating blood cells. Click the player button to begin.

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Cell Differentiation

From a single cell, an organism divides by mitosis to produce lots of identical cells. Then, in a process called cell differentiation, the cells become specialized. For example, some cells become liver cells, some become muscle cells, and some become the skin cells at the tip of your little finger. These cells are specialized to have different structures and perform different functions.

If all these cells are produced by mitosis and have the same genetic information, or DNA, how is it that they can become so different? This is possible because the different cells use different parts of their DNA. DNA has many segments called genes, which contain different directions. When a cell differentiates to become a muscle cell, for example, it only uses the parts of the DNA with directions for muscle cells. Likewise, skin cells only use the part of the DNA information for skin cells.

The process of cell differentiation begins within the first few days that follow conception. Watch The Secret of Life from eMediaVASM to observe how cell differentiation occurs in a fertilized egg. In this video clip, you will watch cells differentiate and become the different parts of the body including a spinal cord, heart, and eyes. It is truly amazing how individual cells work together to create a living organism.

Stem Cells

Before cells become specialized, they are unidentified in form. These cells, known as stem cells, are currently being researched and used to treat disease and medical conditions. However, the current ways that stem cells are harvested and used prompts many ethical questions. In this interactivity, learn about stem cells, the types of stem cells, how stems are used to treat medical conditions, and the ethical questions surrounding the use of stem cells.

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Cell Specialization Review

Review your knowledge of cell specialization in this non-graded activity. Read the directions associated with each question to provide the correct responses. Click the player button to get started.