Schools will see your GPA broken down by year. Frankly, your GPA is totally fine either way. I graduated with a 3.80 cumulative, and ended up with plenty of interviews at awesome programs....clearly a 3.8 is good enough to get your foot in the door. I wouldn't bother explaining - it's the same as how you aren't supposed to "explain" a B you got in a class because it makes you seem kinda crazy. Don't worry, and congratulations on your excellent grades 🙂