Freebase(0.00 / 0 votes)Rate this definition: Ibid. Ibid. is the term used to provide an endnote or footnote citation or reference for a source that was cited in the preceding endnote or footnote. This is similar in meaning to idem, abbreviated Id., which is commonly used in legal citation. To find the ibid. source, one must look at the reference preceding it. Anagrams for ibid. Â»
Fertilization and Embryo Development. Following ovulation, the egg is capable of fertilization for only 12 to 24 hours. Contact between the egg and sperm is random. Once the egg arrives at a specific portion of the tube, called the ampullar-isthmic junction, it rests for another thirty hours. Fertilization â sperm union with the egg â occurs in this portion of the tube. The fertilized egg then begins a rapid descent to the uterus.
How long does it take a sperm to penetrate an egg? It takes a few hours to reach it, and then about 20-30 minutes for a group of sperm to break down the outer membrane of the egg so one can fertilize it. Egg and sperm cells are produced in? Egg is produced in the ovaries in females and sperm in testes in males.