A blood sample contains both testosterone and thyroxine.
Which statement correctly identifies their sources?
Testosterone comes from thyroid; thyroxine comes from testes.
Testosterone comes from testes; thyroxine comes from pancreas.
Testosterone comes from pancreas; thyroxine comes from thyroid.
Testosterone comes from testes; thyroxine comes from thyroid.
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.