why cells within the same organism have the same ADN, but look and function differently?
Sorry, that should be DNA.
Since Jiskha doesn't have any regular biology experts, I suggest you post your question in this forum.
http://biology-forums.com/index.php
Cells within the same organism have the same DNA, or genetic material, because they are derived from a single fertilized egg cell through a process called cell division. However, these cells look and function differently due to a process called cell differentiation.
Cell differentiation is the process by which cells become specialized in structure and function. It allows different cells in an organism to perform specific tasks that contribute to the overall functioning of the organism. The differentiation process is regulated by various factors, including the activation or inactivation of specific genes within the DNA.
To understand why cells look and function differently despite having the same DNA, we need to consider two important concepts: gene expression and cell signaling.
1. Gene Expression: Every cell in an organism contains the entirety of its DNA, but not all genes are active or expressed in every cell. Different cell types activate different sets of genes. For example, in liver cells, genes related to liver function are expressed, while in muscle cells, genes related to muscle contraction are expressed. This selective gene expression allows cells to develop specific features and perform specialized functions.
2. Cell Signaling: Cells communicate with each other through a process called cell signaling. Cells release signaling molecules, such as hormones or growth factors, which can bind to specific receptors on neighboring cells. These signals can influence gene expression and cellular behavior, initiating a cascade of events that eventually leads to cell differentiation. By responding to these signals, cells receive instructions to adopt specific characteristics or functions.
In summary, even though cells in the same organism have the same DNA, they look and function differently because of the regulation of gene expression and the influence of cell signaling. These processes work together to ensure that different cell types are created during development and are maintained throughout the organism's life.