When to cite in biology paper?

I am currently writing biology papers and practically 100% of the information for my report has come from sources other than me. I have paraphrased and used citations, but this has resulted in having citations at the end of every sentence!

I have read online that if something is common knowledge you don't cite it, but what is common knowledge in biology and what isn't? My uni keeps going on about plagiarism and I really don't want to get done for plagiarism lol

If it can be found in a basic biology textbook (e.g. the rate of enzyme activity is increased by temperature up to a point), then you don't need to cite it. If however, the knowledge comes from more advanced specialist textbooks and journals, your should cite. If in doubt, always cite!

Ok, thanks for your reply. Would you say "Molecular Biology of the cell" and "lehninger principles of biochemistry" are basic textbooks or more advanced?