(a(i))[1]
Identify the structure labelled S.
(a(ii))[4]
Name and describe the process that carries food through part S.
(b(i))[1]
Circle the correct words to finish the sentence below. The pH at location U is [higher than / the same as / lower than] that at location T.
(b(ii))[4]
Explain how the pH at location U is influenced by secretions produced by the organs shown in the diagram. Name these organs.