Final answer:
Cells tailor their gene expression in response to external stimuli via signaling pathways that affect transcription. This regulation is crucial for responding to environmental changes and maintaining proper cellular function, and disruptions can lead to diseases like cancer.
Step-by-step explanation:
Cells can change the expression of their genes in response to environmental signals, such as hormones, nutrients, and various external stimuli. These signals often mediate the control of gene expression by influencing the transcription process. The underlying mechanism is regulated by proteins and receptors on the cell's surface, which transmit signals to the cell's nucleus, turning genes on or off. This regulation ensures that cells respond appropriately to changes in their environment, which is critical for processes like development, nutrient uptake, and even the immune response.
For example, hormones released by endocrine glands signal target cells to regulate gene expression that aligns with an organism's needs. Moreover, errors in these regulatory processes can lead to diseases such as cancer, demonstrated by altered gene expression patterns. Understanding how external signals influence gene expression is vital for grasping how cells function and adapt, and also for the development of medical treatments for various conditions.