1. Which of these isn't an external defence?
- Stomach acid
- The immune system
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Other questions in this quiz
2. How does ecstasy affect the level of water in the blood?
- It stops ADH production
- It doesn't
- It increases ADH production
- It decreases ADH production
3. What theory did Darwin come up with?
- The theory of natural selection
- The theory of continental drift
- The theory of genetic mutation
- The theory of reproduction
4. What are all species dependent on?
- The sun
5. What is a species?
- A group of organisms that live in the same environment
- A group of organisms that can successfully breed together
- A group of organisms that can breed together to create fertile offspring
- A group of organisms that look similar