exists and is an alternate of . The sperm that reach the egg swim into it and attempt to penetrate the zona pelluca, which is the semi permeable outer membrane of the egg. Some sperm have a shape which makes this relatively easy, and others which are poorly formed are likely to have more difficulty.
1 Shigellosis is an infectious disease caused by a group of bacteria called Shigella. 2  Symptoms of Shigella infection include diarrhea (often bloody), fever, and stomach cramps starting a day or two after exposure to the bacteria. 3  Shigellosis usually resolves in 5 to 7 days.
Print. Bacillary dysentery, also known as shigellosis, is a potentially dangerous and extremely contagious bacterial infection of the colon. Symptoms develop after an incubation period of one to four days and generally subside within 10 days. (Severe cases may last as long as six weeks, but most cases are mild).hat Causes Bacillary Dysentery (Shigellosis)? 1  The shigella bacillus, a bacterium that invades the lining of the colon, is one of several infections that can cause dysentery. 2  Other causes of dysentery include the parasite amoeba and the bacteria E. coli, Yersinia, and others. 3  The shigella bacillus is typically spread via contact with the fecal ...