Preheat oven to 350°F (175°C). Grease a bundt pan well.
In a bowl, cream together butter and sugar until light and fluffy. Beat in eggs one at a time.
Combine flour, baking powder, baking soda, and salt in another bowl.
Alternately add dry ingredients and milk to the butter mixture, starting and ending with flour.
Stir in lemon juice, zest, and poppy seeds.
Pour batter into the prepared bundt pan.
Bake for about 30-35 minutes, or until a toothpick inserted comes out clean.
Let cool in the pan for 10 minutes, then turn out onto a wire rack to cool completely.
