what are the advantages and disadvantages of internal and external fertilization?
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The close proximity of egg and sperm in internal fertilization increases the likelihood of a successful reproductive cycle. ... Many sperm and eggs die before achieving fertilization. The low success rate of external fertilization puts animals at a reproductive disadvantage compared to internal fertilization.
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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.
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External fertilization is when eggs are released by a female into the environment and later fertilized with a male's sperm. Internal fertilization is when sperm are deposited in or near a female's reproductive tract and fertilization takes place within the reproductive tract.
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The pill works mainly by preventing ovulation or by thickening the mucus surrounding the cervix, which helps block sperm and thins the lining of the uterus so if an egg is fertilized, it would have trouble implanting. The pill is one of the most common forms of birth control.
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['Vasectomies are more effective. ... ', 'Reliable birth control preventing unplanned pregnancy. ... ', 'No need for general anesthesia. ... ', 'Lower health risks. ... ', 'Lower cost than all other forms of birth control. ... ', 'It is a one-time cost. ... ', 'The procedure is often covered by insurance. ... ', 'Does not affect sexual pleasure.']
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As vaginal lubricants have been shown to affect sperm motility in vitro, it is possible that vaginal lubricant use during intercourse may negatively affect natural fertility by inhibiting fertilization.
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Fertilization: When the sperm joins the egg and fertilizes it, conception takes place. Implantation: Seven to 14 days after sex, the fertilized egg attaches itself to the lining of the uterus.
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['IVF helps many patients who would be otherwise unable to conceive. ... ', 'It has been used for a long time and has a safe track record. ... ', 'IVF can be more successful than IUI and other forms of assisted reproductive technology. ... ', 'It can help single women and same-sex couples.']
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['volume.', 'motility.', 'shape.', 'ability to pass through the cervical mucus and make it to the egg.', 'acrosome reaction.', 'zona pellucida binding.', 'nuclear decondensation.']
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['Gametogenesis, the generation of egg cells (oogenesis) or of sperm (spermatogenesis);', "Fertilization, the entry of the sperm cell into the egg cell, followed by the union of the two cells' nuclei;", 'Embryogenesis (embryonic development) with. ... ', 'Metamorphosis to an imago or adult.']
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Unlike the simpler process of artificial insemination -- in which sperm is placed in the uterus and conception happens otherwise normally -- IVF involves combining eggs and sperm outside the body in a laboratory. Once an embryo or embryos form, they are then placed in the uterus.
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Facts about timing Ovulation is when a mature egg is released from the ovary. The egg then moves down the fallopian tube where it can be fertilised. If sperm are in the fallopian tube when the egg is released, there is a good chance that the egg will be fertilised, creating an embryo, which can grow into a baby.
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Fertilization: A Sperm and an Egg Form a Zygote They each contain half the genetic information necessary for reproduction. When a sperm cell penetrates and fertilizes an egg, that genetic information combines. ... The zygote starts to divide and multiply.
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A study involving more than 18,000 women showed multivitamins - particularly folic acid - improve a woman's fertility. Those taking a supplement regularly had a 40 per cent lower risk of suffering problems producing eggs - the second biggest cause of female infertility.
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There are no physical side effects, and you can use it to plan when you get pregnant. You have to keep a daily record of your fertility signals, such as your temperature and the fluids coming from your cervix – it takes 3 to 6 menstrual (monthly) cycles to learn the method.
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FACT: To get pregnant, you need two things: an egg and a sperm to fertilize that egg. As long as you still have eggs, they can still be fertilized. You can get pregnant, go through a full-term pregnancy, and have a healthy child. However, conceiving is a complex process, especially for women over 35.
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It can easily be done at home. But with IUI, the sperm is deposited directly into the uterus, so its journey to the fallopian tubes is much shorter than it is with intracervical insemination.