Bit of exam technique. They tend to be picky on the mark scheme regarding the wording, that's why memorisation-type learning comes into play a fair bit. Past papers make the biggest difference.
Understand and explain something perfectly, but don't use the 2-3 key words they want, they won't give you full marks on a question. I've been caught out like that, it's nonsensical.
You need to follow what's happening, as it will make it easier to remember things, but a lot of the exam questions will be recall - so list the X steps in this process, label this, and occasionally 'explain' questions, which really breaks down to just linking a couple of points together.