1. VIRUSES

2. SOME SCIENTISTS THINK VIRUSES ARE LIVING THINGS, AND SOME DO NOT. THEY ARE MUCH SMALLER THAN A CELL AND DO NOT HAVE ORGANELLES. IN FACT, A CELL CAN HOLD OVER 500 VIRUSES! VIRUSES ARE SO SMALL SCIENTISTS KNEW THEY EXISTED LONG BEFORE THEY COULD SEE THEM. THEY COULD NOT BE SEEN UNTIL THE 1930’S WHEN AN ELECTRON MICROSCOPE WAS INVENTED BY ERNST RUSKA. LABEL THE PARTS OF A VIRUS. INSIDE A VIRUS IS ITS GENETIC INFORMATION. THIS IS THE PROGRAMMING A VIRUS NEEDS TO REPRODUCE ITSELF. THE OUTSIDE OF A VIRUS IS A PROTEIN COAT THAT PROTECTS THE GENETIC INFORMATION AND HELPS IT ATTACH TO CELLS.

3. VIRUSES CONTINUE.. VIRUSES CAN ONLY DO ONE THING- REPRODUCE. THEY MUST USE A HOST CELL TO REPRODUCE. A VIRUS CAN ONLY INFECT ONE CELL. ITS RECEPTORS ONLY FIT ONE PARTICULAR TYPE OF CELL, JUST LIKE A KEY ONLY FITS ONE LOCK. EXPLAIN HOW A VIRUS INFECTS A CELL: VIRUS ATTACHES ITSELF TO A CELL. INSERTS ITS GENETIC MATERIAL. THE GENETIC MATERIAL TAKES CONTROL OVER THE CELLS FUNCTIONS. THE CELL BEGINS MAKING MANY COPIES OF THE VIRUS. THE CELL BURSTS RELEASING THE VIRUSES INTO THE BODY. THE VIRUSES EACH SEEK OUT A NEW CELL.

4. YOUR IMMUNE SYSTEM MOST VIRAL DISEASES ARE CONTAGIOUS. THEY CAN BE PASSED FROM ONE PERSON TO ANOTHER. SOME ARE PASSED THROUGH THE AIR BY COUGHING AND SNEEZING. SOME ARE PASSED THROUGH BODY FLUIDS LIKE BLOOD. SOME ARE SPREAD BY DIRECT CONTACT LIKE SHAKING HANDS. YOUR BODY HAS A DEFENSE SYSTEM TO PROTECT ITSELF FROM VIRUSES CALLED AN IMMUNE SYSTEM. LIST THE PARTS OF YOUR BODY’S IMMUNE SYSTEM SKIN WHITE BLOOD CELLS ANTIBODIES T-CELLS INTERFERON

5. ONCE YOU HAVE HAD A VIRUS AND RECOVERED, YOU CANNOT GET THE SAME VIRUS AGAIN. YOUR BODY WILL HAVE MADE ANTIBODIES SPECIFICALLY DESIGNED TO PROTECT YOU FROM THAT PARTICULAR VIRUS. THE ANTIBODIES BLOCK THE CELL, SO THE VIRUS IS UNABLE TO ATTACH TO IT. YOU CAN SLOW THE SPREAD OF VIRUSES BY: WASHING YOUR HANDS COVERING YOUR MOUTH AND NOSE WHEN YOU SNEEZE OR COUGH. AVOIDING DIRECT CONTACT WITH THOSE THAT ARE SICK GETTING ENOUGH SLEEP KEEPING YOUR BODY HEALTHY

6. VIRUSES ARE HELPFUL AND HARMFUL VIRUSES ARE BOTH HELPFUL AND HARMFUL HELPFUL: SOME INFECTIONS ARE HELPFUL, SINCE THEY INCREASE A PERSON’S IMMUNE SYSTEM. HARMFUL: DISEASE: CHICKEN POX COMMON COLD POLIO MEASLES MUMPS RABIES WARTS COLD SORES SOME CANCERS FLU