Yeoman Martha Landon?
1) She is a yeoman, yet is on the landing party in a research capacity. 
2) She worries about the ship and the deaths of the redshirts. 
3) She is a romantic along with Chekhov. She appears to be a little naive on certain procreation matters, suggesting she *may*  believe in no sex before marriage (???), as opposed to a more 'modern' outlook on love (???)