Cellular stress responses are mechanisms that cells activate when they encounter harmful conditions, such as extreme temperatures, toxins, or lack of nutrients. These responses help cells adapt and survive by altering their functions, repairing damage, or even triggering cell death if the stress is too severe. Key components of cellular stress responses include heat shock proteins, which help refold damaged proteins, and antioxidants, which neutralize harmful free radicals. Additionally, cells may activate signaling pathways that promote survival or initiate repair processes, ensuring their proper functioning under adverse conditions.