Are whooping cough and the croup caused by the same virus or bacteria?

No. Whooping cough is caused by the highly contagious, but vaccine preventable bacteria bordetella pertussis. Croup is usually caused by respiratory viruses with parainfluenza being most common.
No. Whooping cough is caused by the bacteria bordatella pertussis, which is a vaccine preventable disease. It can be treated with antibiotics if acquired and antibiotics can be given to those exposed to try to prevent disease. Croup, on the other hand, is typically caused by one of a number of viruses. Rarely, bacteria may cause croup.