The meteorite was probably 1<span>0 to 15 km (6.2 to 9.3 mi) wide</span> and affected the entire planet through a proces called "impact winter". As the name suggests, an impact winter is a period of low temperature produced by a huge cloud of ash and dust that blocks sunlight. Since sunlight is essential for plants to survive, if the sun rays are blocked by this cloud, all animals that depend on those plants (including dinosaurs) will die. The meteorite could have created such a cloud upon hitting the earth.
Cyanobacteria, Anabaena and Azotobactor are called Nitrogen fixing bacteria. These bacteria change the nitrogen in the atmosphere into a form that is used by the plants to make proteins. Plants take nitrogen in the form of nitrates. The atmospheric nitrogen is first converted into ammonia after that ammonia is converted into nitrates and this nitrates use by the plants to make proteins.
