The union of the (haploid) male and (haploid) female germ cells (sex cells or gametes) to produce a diploid zygote. Fertilization marks the start of development of a new individual (organism), the beginning of cell differentiation.
The process by which the pollen causes the embryo to become fertile. Conception.
The union of an egg (ovum) and a sperm, which normally takes place in a woman’s fallopian tube, the sperm (one of millions released in an ejaculation) having traveled from the vagina through the cervix and uterus to the site. A single sperm burrows through the two outer layers of the egg, at which point the egg’s membrane immediately bars the way to other sperm. The resulting fertilized egg is called a zygote. If two sperm enter, the egg will not be viable, having lethal duplication of DNA, and a spontaneous abortion will occur, so early that the tissue will probably simply be reabsorbed by the body or flushed out in menstruation. (The same is true of many other fertilized eggs that have defects so severe that they are clearly, at a very early stage, incompatible with life.) If two eggs are fertilized by two different sperm, the result will be dizygotic, nonidentical, or fraternal twins; if a zygote separates into two separate EMBRYOS, the result is monozygotic or identical twins.
Union (fusion) of the male and female sex cells (gametes, the spermatozoon and ovum) to form a single cell (zygote) that then divides to eventually form the fetus.
Union of a sperm and egg that develops into an embryo.
The union of an egg with a sperm. Fertilization produces the first cell of a zygote, with half of the genes from the mother and half from the father. The zygote becomes an embryo, which then develops into a fetus.
The fusion of a spermatozoon and an ovum. Rapid changes in the membrane of the ovum prevent other spermatozoa from penetrating. Penetration stimulates the completion of meiosis and the formation of the second polar body. Once the male and female pronuclei have fused the zygote starts to divide by cleavage.
The process by which male and female gametes (spermatozoa and oocytes respectively) fuse to form a zygote which develops, by a complex process of cell division and differentiation, into a new individual of the species. In humans, fertilization occurs in the fallopian tubes. Sperm deposited in the upper vagina traverse the cervix and uterus to enter the Fallopian tube. Many sperm attempt to penetrate the zona pellucida surrounding the oocyte, but only one is able to penetrate the oocyte proper and this prevents any other sperm from entering. Once the sperm has entered the oocyte, the two nuclei fuse before the zygote begins to divide.
The process that begins with the penetration of the secondary oocyte by the spermatozoon and is completed with the fusion of the male and female pronuclei. This usually takes place in the fallopian tube. Viable spermatozoa have been found in the tube 48 hr after the last coitus. After the ovum is fertilized and the diploid chromosome number is restored in the zygote, cell division begins. The blastocyst then enters the uterus, where it may implant for continued nurture and development.
The process by which a sperm and an egg and their genetic material join to create a new human life.
Fertilization is the process of the sperm and ovum (egg cell) coming together. In natural fertilization, this union occurs in the woman’s fallopian tube after sexual intercourse.
Fertilization can also happen through artificial means, such as introducing semen into the cervix, or it may occur in a laboratory setting.