An account can be a narration or description, arrangement with a bank, assets of that arrangement, method for obtaining goods on credit, financial record keeping, counting or reckoning. If you have to account for something you must give an explanation.
It can refer to a proportion eg romances account for at least half of my stories* or it can mean to kill or dispose of. I haven't ever heard it used in that way - have you? Another use is to consider or regard. Eg he was accounted guilty.
If you are of some account you're considered as important. My husband is of some account to me. I met him when I worked as an accounting assistant and accounted for the money he wanted to spend. There are several ways he gives a good account of himself, but I'll take into account the fact you may not want all the details.
*I've no idea if that's true as I don't account for each genre separately.
Win this competition and you can pay £2500 into your bank account. (I'm sure the judges will take the personal statement into account, so on no account forget to include it)