What is judicial review and how does it challenge parliamentary sovereignty?

Judicial review refers to the process by which the actions of the legislative and executive branch can and are subjected to be viewed by the judicial branch. Such a process is present in order to ensure that the branches mentioned do not exceed its limits and thus, can be recognised as a mechanism of checks and balances within the constitution. Judicial review challenges parliamentary sovereignty because it holds the parliament accountable in the way that it does not abuse its powers.