How hard is biological science in uc davis?

BioSci is not one of the easier majors, I will tell you right off the bat. Try it. Take the cl, see how it is. It is your life that you are living. If you do not enjoy the topic, then do not do it. However, I would not take other people's warnings with more than a grain of salt. This is an experience you need to have on your own. Try. See if it is too hard. Then work harder and see if it is still too hard. Only you can make up your own mind.