Preheat oven to 350 degrees F (175 degrees C). Grease and flour a fluted tube cake pan.
Beat cake mix, sour cream, vegetable oil, lemon juice, eggs, pudding mix, zest, poppy seeds, and lemon extract in a bowl with an electric mixer on low speed for 1 minute. Increase speed to medium and beat for 3 minutes. Pour batter into prepared pan.
Bake in preheated oven until a toothpick inserted into the center comes out clean, about 45 minutes. Cool in the pan for 10 minutes before removing to cool completely on a wire rack.
