The University of California website states that one of the factors considered in admission is “UC-approved” honors, AP and IB courses and that extra weight is assigned to grades received in honors courses. You should check with the counselor of the high school you’ll be attending to find out if the honors biology course meets this requirement. UC also considers “academic performance related to opportunities available in your high school" which suggests that taking advantage of rigorous courses will improve your standing.
You will also need to ask a counselor about enrolling in honors courses as a 10th grader if you don’t do so in 9th grade. However, I think that starting out in honors courses will be beneficial if you plan to enroll at some point in high school. Students in their second year of honors courses will have already learned the expectations and adjusted to the rigor.
Biology is the study of life. You’ll likely be learning about plants, animals, cells, genetics and ecology. It’s likely that the curriculum for honors biology is similar to or the same as the regular biology curriculum. An honors section of a course usually involves learning concepts in more depth. You’ll probably be expected to spend more time outside of class on assignments for honors biology. Honors courses are designed to help prepare students for college, so some independence and self-motivation will be expected. Does your high school have an orientation day for freshmen in advance of registration? If so, this would be a good opportunity to meet the biology teachers and talk to them about the courses offered.
The benefit of taking honors courses in high school extends beyond college admission. You’ll be better prepared for the rigor of college coursework if you challenge yourself in high school. You’ll have the opportunity to learn study skills and time management. Do you know any college students who are graduates of your high school? If so, contact one and ask about his or her high school experience. Students who take challenging courses in high school usually have an easier time in college and are appreciative, although belatedly, of the hard work that was required of them in high school.
I know this doesn’t directly answer your question as I can’t speak for colleges, but I hope it gives you some direction in making your decision. Don’t forget to talk to your parents about your opportunities and choices.