. Elementary biology; an introduction to the science of life. Biology. SEX 299 called fertilization. The essential thing about fertilization is the uniting of two different nuclei into one. What the meaning of this process is in the life of organisms we do not know with certainty. We know some of the effects of the process, and we can tell what conditions lead up to it in some b c Fig. 131. Reproduction in rockweed, or bladder wrack 17, expansions of the rockweed containing the gamete organs ; b, section of an egg-bearing organ ; c, the large gamete, or egg, with large, distinct nucleu
. Elementary biology; an introduction to the science of life. Biology. SEX 299 called fertilization. The essential thing about fertilization is the uniting of two different nuclei into one. What the meaning of this process is in the life of organisms we do not know with certainty. We know some of the effects of the process, and we can tell what conditions lead up to it in some b c Fig. 131. Reproduction in rockweed, or bladder wrack 17, expansions of the rockweed containing the gamete organs ; b, section of an egg-bearing organ ; c, the large gamete, or egg, with large, distinct nucleus and food granules ; d, the small gamete, or sj>enn, having the shape of a pear and bearing motile cilia. Sperms swarm around an egg until one of them unites with the egg. After the conjugation the zygote develops into a new individual 349. Male and female. The gametes that are so unlike as we have seen them to be in the rockweed are distinguished by special names. The large gamete is sometimes called the oospJierc, or &gg cell. The small one is called the spermatosoid, or the sperm cell. We sometimes distinguish the two gametes by calling the large one the female and the small one the male. Most of the familiar plants and animals reproduce by means of male and female gametes, forming zygotes. This kind of reproduction is called sexual reproduction, in distinction from reproduction by spores, which is called asexual; that is, without sex. There are many animals and very many plants that repro- duce both sexually and asexually (see Chapter LXI),. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Gruenberg, Benjamin C. (Benjamin Charles), 1875-1965. Boston New York [etc. ] Ginn and company
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