Year 8 Science · Unit 1 · Lesson 16
Challenge Worksheet
Learning Goals
What if…?
Scenario
Imagine a person lives and works in an environment where the outside temperature changes dramatically throughout the day, from very cold in the morning to extremely hot in the afternoon. The person needs to keep their body functioning effectively throughout the day. Their body constantly responds to outside conditions to keep important internal conditions within a suitable range. However, on one very hot afternoon, they are unable to access water or shade, and their water balance begins to fall outside the suitable range. Within a few hours, their body function starts to be affected.
Using what you know about homeostasis and the idea of a "suitable range," predict and explain what consequences falling outside the suitable range for water balance would have for this person's body function. Use the terms "homeostasis," "suitable range," and "internal conditions" in your answer.
1. The lesson says that homeostasis is a "systems idea", it depends on several parts of the organism working together, not one structure acting alone. Using body temperature as your example, explain why no single structure could maintain homeostasis on its own. What does this tell us about how living systems are organised?
2. How does homeostasis connect to the ideas about system disruption from Lesson 15? Explain how a disruption in one system component could make it harder to keep internal conditions within the suitable range. Use an example to support your answer.
Wrap Up
In one sentence, what was the main idea of this lesson?