how does repetition of lexemes such as "stress" (6, 7) and "patience" (8, 11) and "control" (12, 13) create cohesion? (according to assess report those were the line numbers)
Well you probably know that cohesion refers to the how the elements in the sentences are explicitly 'glued' together. A common cohesive cue is the use of lexemes from the same lexical field together with synonymy and antonymy. Here, 'patience' and 'control' originate from the same lexical field that is associated with endurance, resignation etc.. When 'stress' (an antonym to patience) is used within close proximity of these terms, it allows readers to subconsciously identify lexical chains and alert them to the words that bind the text together, thus creating cohesion.
I haven't done the 2011 exam yet so you probably have more info that is relevant to the text that can be added on to what I'm saying