Maybe these two references, from that article, will fill in any gaps you still have:
^ Wing R, Drew H, Takano T, Broka C, Tanaka S, Itakura K, Dickerson R (1980). "Crystal structure analysis of a complete turn of B-DNA". Nature 287 (5784): 755–8. Bibcode 1980Natur.287..755W. doi:10.1038/287755a0. PMID 7432492.
^ a b Pabo C, Sauer R (1984). "Protein-DNA recognition". Annu Rev Biochem 53: 293–321. doi:10.1146/annurev.bi.53.070184.001453. PMID 6236744.
Or perhaps, you'd like to review your textbook, or class notes.
I'm sorry I wasn't able to be more helpful, but that is what we do here: we help, we try to give hints, so you learn for yourself, and you're better off, come exam time, when you have to quickly write an essay on the topic to show your knowledge. There is very little we can do, when you ask a very general definition question, except read a textbook for you, and dump the answer. You might also want to peruse the Forum Rules, posted in red, at the top of every page.
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Topic: What are major and minor grroves in DNA ?? (Read 3707 times)