When you wake up in the morning, you usually haven't eaten for 8-12 hours. That's why it's important to load up on energy to get through the afternoon. This first meal of the day is called break-fast because it literally breaks the nightly fast. The bodies metabolism switches into a higher gear. Research shows that both children and adults learn and perform better in school and at work if they had a good breakfast that morning.
Breakfast also helps with controlling your weight. Skipping breakfast can cause people to overeat later in the day, which in combination with lower (sleep-mode) metabolism, can disrupt the caloric balance. Eventually leading to a caloric excess at the end of the day.
Since a good breakfast will provide plenty of nutrients and energy you won't get sudden hunger and dizziness during the afternoon. Skipping breakfast can lead to irritability and tiredness, so feed the body to wake it up.
And make sure to rehydrate as well, your body loses a lot of fluids during a good night's sleep.