The Figure shows how a hormone travels from an endocrine gland to its target organ.
Figure

Describe how the hormone leaves the endocrine gland.
The hormone passes through organ P and organ Q, but only the target organ responds.
Suggest why.
Explain why the hormone can affect a target organ that is a long way from the endocrine gland.
Endocrine glands have a very good blood supply.
Suggest why.
42 exam-style questions on Edexcel GCSE Biology 7.1 Hormones and coordination, covering 7.1.1 Endocrine glands and hormone transport, 7.1.2 Adrenalin and fight or flight, and 7.1.3 Thyroxine and negative feedback. Each one has a worked solution and a mark scheme showing where the marks go.