How do organisms cope with stressful external environmental conditions which are localised or of short duration ?

Explanation

**Step-by-Step Solution:**

1. **Understanding the Context**: Organisms face various external environmental conditions that can be stressful. These conditions can be either permanent or temporary. The question focuses on how organisms cope with stressful conditions that are localized or of short duration.

2. **Regulation vs. Conformation**:
- When faced with permanent stressful conditions, organisms have two main strategies: regulation and conformation.
- **Regulation**: This involves maintaining homeostasis, where organisms keep their internal environment stable despite external changes. This process requires significant energy and is not feasible for many organisms.
- **Conformation**: Many organisms conform to their environment, adapting through morphological, physiological, or behavioral changes to survive in unfavorable conditions.
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