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.
Shigella Species. Escherichia coli. Intestinal infections can mimic the classic endoscopic and clinical (abdominal pain, diarrhea, and weight loss) features of IBD, and can present with identical extraintestinal manifestations (eg, reactive arthritis, erythema nodosum).