Sociology is tested on the MCAT in the psych/soc section, but it is not a huge portion. You will be able to learn all the sociology you need for the MCAT on your own, using online resources like Khan Academy or MCAT prep textbooks like Kaplan, TPR, etc. However, if you take the class, you won’t have to study sociology much at all before the MCAT due to the depth of knowledge you will have from class!
If you have already taken the MCAT, sociology is still a highly recommended class to take for premeds due to the importance in the content matter. It will come in handy in medical school interviews as well as once you actually go into the workforce! The three sociology options at UMich are SOC 100, SOC 300, and SOC 302. 

• SOC 100 is recommended for freshman and sophomores (underclassmen) who just want to take a basic introduction to sociology. It has a discussion section and is 4 credits.
• If you are an upperclassman who has never taken sociology, SOC 300 is usually recommended. It covers the exact same material as SOC 100 but is only 3 credits because it doesn’t include a discussion section. The professor is often the same for SOC 100 and SOC 300 so you can assume the level of difficulty will be comparable.
• Finally, SOC 302 is another introduction to sociology class that assumes no past experience with the material. It is, however, geared toward those interested in health and medicine, such as premeds. Sarah Burgard is also a great professor who teaches this course in the fall and I would definitely recommend it!