Why are a plant's stomata generally open during the day and closed at night?

image result for how many calories of energy will 20 grams of carbohydrates provide in one gram provides 4 calories

consuming the right balance of protein, carbohydrates and fat can you maintain a healthy weight and optimize your energy levels. protein and carbohydrates both contain 4 calories per gram, while fat provides 9 calories per gram.

1. efficient use of space

2. elimination of groundwater contamination

3. energy generation

4. lower carbon footprint