No that is absolutely 100% wrong. Those sizes are not quantitative data and mistaking this kind of 'quantitized' data for actual quantitative data is among the most common mistakes in statistics. Data is only really quantitative if there is an actual quantity being measured. Height, weight, number of something, duration. Things like 'rate on a scale from one to ten' are actually quanlitative data masking as quantitative data. There is no scale calibration, no useful sense in which a 4 is 'twice as good' as a 2. One has simply used numbers to create the illusion of measurement. Applying, say, a linear regression to this sort of data is going to be questionable at best, misleading at worst. Now if those sizes weren't made up, but an actual body measurement, like mens pants or suits, then you've got quantitative data. A result of this is that a great deal of statistical reasearch done by amateurs in business contexts is pretty untrustworthy. It is no surprise to me a instructor got this wrong. I'm honestly very impressed you saw through it. Most people actually believe throwing numbers into something makes it magically rigorous. You are now definitely smarter than most MBAs! More on reddit.com

'Quantitative biology' is really a fuzzy term, I mean counting frogs can be considered quantitative biology but this is not what they likely mean. It seems to me that, in this case, bioinformatics has been sliced out of the larger biological field to a special program. When I was entering grad school I was advised to dabble in genetics (bioinformatics had yet to be a commonly used term). Now, many years and a revolution of the field later, my advice to new students is to make sure to get adequate experience in biology if you think you want to be in bioinformatics. There is an army of new students and scientists that want to use big data and fancy algorithms to extract inferences from genetic data but a dearth of people who can connect the technique to the principles behind them. A master's degree should serve both as a stand-alone degree and/or as a stepping stone to a PhD program. In both scenarios, a firm grasp of 'quantitative biology' will assist you greatly. Ultimately, I'd reach out to contacts in the department (ideally other grad students) and ask about the difference and how one or the other might suit you better. More on reddit.com