Before the dawn of vaccines, the human body was left on its own to battle invaders. Vaccines jump-start the immune response so the body can fend off a real attack later.
See how a vaccine mimics the pathogen and triggers a chain reaction in the immune system that the body remembers.
When it comes to rodent pets, hamsters and gerbils fit the description of cute and frisky. These animals originated in Africa, the Middle East, and Asia. Siberian hamsters and Mongolian gerbils are popular pet species.
The nocturnal pet hamster may run up to 8 miles a night in its wheel. The gerbil takes naps, but can be active 24/7, and is more social than the solitary hamster.
How many people in your life have died of an infectious disease? Almost anyone answering that question before the 20th century would have said, "many."
Vaccinations, antibiotics, and hygiene have changed our lives. But the microbes are changing too. New diseases are emerging, as old ones evolve to resist the drugs that used to kill them. Take a look at the fight.
It could fit in your living room, and blow up a city. And that was the world’s first nuclear bomb, used in 1945. Some of today’s “thermonuclear” weapons are 1000s of times more powerful.
How do these terrifying devices release the energy in atoms? How do they go on killing after they’ve exploded? And how were scientists going to use them to explore space? Get the details on "nukes."