Cell Differentiation & Stem Cells

READ ME to understand how cells become specialized! Cellular differentiation is the process by which a cell becomes a more specialized cell type. Different complex systems of tissues have different kinds of cells.Differentiation dramatically changes a cell's size, shape, metabolic activity, and responsiveness to signals. These changes are largely due to highly-controlled gene expressions (turning a gene on or off). With a few exceptions, cellular differentiation almost never involves a change in the DNA itself. It does involve switching off many genes not needed in a particular tissue. Thus, cells in different tissues may have very different physical characteristics despite having the same genes (sections of DNA that code for a trait).Turning genes on and off allows the cells to produce proteins that are necessary for the changes in the way those cells look and function. For instance, the development of the retina pushes the development of the lens and cornea of the eye. The substance secreted by the developing retina can only diffuse a short distance and affect the neighboring cells, which become other parts of the eye. The patterns of gene expression are specific to cell types and are directly responsible for the differences between the functions of different cells.How do different cell types decide which genes to turn on or off?This is the result of processes occurring during embryo development. As the embryo begins to divide, the presence of chemicals and hormones starts altering the decisions as to which genes will be turned on or off. As some of the genes in some of the cells turn on, they may code for proteins that slowly diffuse through the developing embryo.A cell that is able to differentiate into many types of cellsis known as an EMBRYONIC stem cell. ADULT stem cells maintain and repair the tissue in which they are found after development (they've already been given a specialized job).Stem cells are different from other cells in the body in three ways:They can divide and renew themselves over a long timeThey are unspecialized, so they cannot do specific functions in the bodyThey have the potential to become specialized cells, such as muscle cells, blood cells, and brain cellsThat is why embryonic stemcell research is much more promising thanAdultstem cell research. Types of stem cells Use the article and the video links you were provided to match the terms with their correct definition. Adult Stem Cells Stem Cells that maintain and repair the tissue in which they are found after development (they've already been given a specialized job). Embryonic Stem Cells Stem Cells that are able to differentiate into many different kinds of cells.(They have not yet been given a specialized job). cell differentiation the process through which a cell undergoes changes to become a more specific type of cell with a specific function gene expression the process by which the information encoded in a gene is used to create a protein molecule which then leads to the development of a trait or characteristic What are genes? HINT: see paragraph 2. sections of DNA that code for a trait your entire genome stages of embryo development stem cells How do cells differentiate to become different kinds of cells?HINT: see paragraph 2 3. different genes turn on by turning on a gene, different proteins are made proteins will promote how the cells look and their functions all of the above none of the above What are embryonic stem cells?Hint: see the last paragraph cells that can differentiate into any type of cell cancer cells sections of DNA that code for a trait embryo development I'm Done With Reading! That's fair. That was some heavy text we just read, with lots of new information. Let's take a brain break and watch this video on HOW and WHY cell specialization is so important! [VIDEO link] After watching this video you will be able to answer the following questions successfully. Why are gametes like eggs and sperm considered "highly specialized"? Hint: there are two answers you need to choose here! they have a specific size and shape they have specific sub-structures that allows it to do its function they are weak they form embryos When you've become an adult, where can you find some undifferentiated cells? Bone marrow so it can differentiate into red blood cells muscles nerve cells sperm What makes muscles cells specialized? Hint: there are two right answers here! they have lots of mitochondria for energy and power they can contract they make red blood cells they are not specialized Why are scientists so pressed to get their hands on some stem cells? They can repair damage to cells that can never grow back like nerve cells and brain cells they can be cloned in the laboratory they can specialize into the specific cells that we need All of the above none of the above