From the Cycles view, you can track execution stats, such as progress, effort, issues raised, etc.
If a defect has been created and attached to a step in a test cycle, you can hover over the issue link to view a link to the defect. (Note that to view defect links, you must have Issues selected as one of your columns options.)
Just hover over the issue link:
And a link to the defect appears in a tooltip.