Uni in the UK: Thank you, you answered my questions perfectly. I will definitely not be putting in hobbies. It's pointless, and IMO the admissions committee could give a crap! I have plenty of more relevant things to talk about.
adam0311 and alexs2602: Haha, thanks for the defense. Although, since I have a degree in biology I have to assure you that 'life science' is not psudointellectual. It's a catch all term for biologically related sciences like genetics, ecology, mircobiology, bacteriology, virology, cell biology...basically it comes from the fact that there are so many subfields of biological science.
It happens with other sciences too. For example, ones like geology, oceanography, etc. have the catchall term 'earth science', and ones that aren't directly related to living things like physics fall under the term 'physical science'. However, there's so much overlap between the three that the categories are really kind of pointless.