Biology AQA a level mark scheme

Hi guys I have a question discussing the biology AQA mark schemes.
1. Firstly do they deduct marks for extra information. For example, I wrote 'carboxyl group' rather than carboxyl which is what was written in the mark scheme for a one marker. I assume it is because the question said 'group' so they didn't want me to reinstate it? But it is still technically right therefore will I get a mark? (PS i know it sounds stupid but I don't want to lose silly marks).

2. Secondly, If I write extra info, for example in a 4 marker, but it is wrong and the other 4 marks are all mentioned, then will I still get all the marks despite the wrong point?

1. carboxyl group will still get u the mark!

2. they cant mark you down unless you make points that contradict each other, e.g. if u wrote two opposites in the hopes that one will be right, im pretty sure they can give you 0 marks. but anything extra that doesnt contradict ur other points they just ignore it and it doesnt affect ur mark