| 释义 |
yolk
yolkthe yellow of an egg
Not to be confused with:yoke – a working frame for oxenyolk Y0023200 (yōk)n.1. a. The portion of the egg of egg-laying vertebrates, such as reptiles and birds, and of certain invertebrates that consists chiefly of protein and fat and serves as the primary source of nourishment for the early embryo.b. This portion of the egg of a bird, especially a chicken, which is large, yellow, and surrounded by albumen.2. A greasy substance found in unprocessed sheep's wool, which is refined to make lanolin.
[Middle English yolke, from Old English geolca, from geolu, yellow; see yellow.]
yolk′y adj.yolk (jəʊk) n1. (Zoology) the substance in an animal ovum consisting of protein and fat that nourishes the developing embryo. 2. (Zoology) a greasy substance secreted by the skin of a sheep and present in the fleece[Old English geoloca, from geolu yellow] ˈyolkless adj ˈyolky adjyolk (yoʊk, yoʊlk)
n. 1. the yellow and principal substance of an egg, as distinguished from the white. 2. the part of the contents of the egg of an animal that enters directly into the formation of the embryo, together with any material that nourishes the embryo during its formation. 3. a natural grease exuded from the skin of sheep. [before 1000; Old English geoloca, derivative of geolu yellow] yolked, adj. yolk′y, adj. yolk (yōk) The yellow internal part of the egg of a bird or reptile. The yolk is surrounded by the albumen and supplies food to the developing young.yolkThe part of animal egg cell that serves as a food source for the embryo.Thesaurus| Noun | 1. |  yolk - the yellow spherical part of an egg that is surrounded by the albumenegg yolkfixings, ingredient - food that is a component of a mixture in cooking; "the recipe lists all the fixings for a salad"eggs, egg - oval reproductive body of a fowl (especially a hen) used as food | | 2. |  yolk - nutritive material of an ovum stored for the nutrition of an embryo (especially the yellow mass of a bird or reptile egg)vitellusfood, nutrient - any substance that can be metabolized by an animal to give energy and build tissueegg - animal reproductive body consisting of an ovum or embryo together with nutritive and protective envelopes; especially the thin-shelled reproductive body laid by e.g. female birds |
Translationsyolk (jouk) noun (also ˈegg-yolk) the yellow part of an egg. The child will only eat the yolk of an egg – she won't eat the white. 蛋黃 蛋黄yolk
under the yolkUnder or at the mercy of an immense and oppressive force, burden, or pressure. (A common misspelling of the correct phrase, "under the yoke.") Thousands of people are estimated to have lost their lives under the yolk of the brutal dictatorship. Under the yolk of misogyny, racism, and homophobia, a gay woman of color will inevitably face an immense amount of discrimination in our society.See also: yolkyolk n. semen. (Possibly confused with egg white.) Clean up that yolk before somebody sees it. yolk
yolk1. the substance in an animal ovum consisting of protein and fat that nourishes the developing embryo 2. a greasy substance secreted by the skin of a sheep and present in the fleece Yolk (deutoplasm), a nutritive substance that accumulates in the ovum of animals and man in the form of granules or membranes that sometimes merge into a solid yolk mass (in insects, bony fish, and birds). Yolk has been discovered in the ova of all animals and man, but its quantity and distribution vary considerably. In ova with a small amount of yolk, the yolk particles are distributed evenly throughout the cytoplasm (isolecithal ova). In ova with a large amount of yolk, the yolk particles are concentrated either in the vegetative part of the ovum (telolecithal ova) or in the central part of the cytoplasm, around the nucleus (centrolecithal ova). The type of egg cleavage depends on the quantity and distribution of the yolk. Chemically there are three principal varieties of yolk: protein, fat, and carbohydrate. However, in most animals the yolk granules have a complex chemical composition and contain proteins, fats, carbohydrates, ribonucleic acid, pigments, and mineral substances. For example, in the mature hen’s egg, the yolk contains 23 percent neutral fat, 16 percent protein, 11 percent phospholipids, 1.5 percent cholesterol, and 3 percent minerals. Various organelles of the ovum participate in the synthesis and accumulation of the yolk: the Golgi apparatus, endoplasmic reticulum, and mitochondria. In many animals the protein component of the yolk is synthesized outside the ovary and enters the growing ovum by means of pinocytosis. In some invertebrate animals the yolk may also accumulate in special cells of the ovary—the yolk cells, on which the developing embryo is nourished. T. B. AIZENSHTADT yolk[yōk] (biochemistry) Nutritive material stored in an ovum. The yellow spherical mass of food material that makes up the central portion of the egg of a bird or reptile. yolk
yolk [yōk] the stored nutrient of the ovum.yolk (yōk, yōlk), 1. One of the types of nutritive material stored in the oocyte (ovum) for the nutrition of the embryo; yolk is particularly abundant and conspicuous in the eggs of birds. Synonym(s): vitellus2. Fatty material found in the wool of sheep; when extracted and purified, it becomes lanolin. [A.S. geolca; geolu, yellow] yolk (yōk)n.1. a. The portion of the egg of egg-laying vertebrates, such as reptiles and birds, and of certain invertebrates that consists chiefly of protein and fat and serves as the primary source of nourishment for the early embryo.b. This portion of the egg of a bird, especially a chicken, which is large, yellow, and surrounded by albumen.2. A greasy substance found in unprocessed sheep's wool, which is refined to make lanolin.
yolk′y adj.yolk (yōk) 1. One of the types of nutritive material stored in the oocyte for the nutrition of the embryo; particularly abundant and conspicuous in the eggs of birds.
Synonym(s): vitellus. 2. Fatty material found in the wool of sheep; when extracted and purified, it becomes lanolin. [A.S. geolca;geolu, yellow]yolk the food store in the eggs of the majority of animals, made up mainly of fat and protein granules. It must contain all the essential ingredients for the entire development of the embryo. Where yolk is present in the egg, as in chickens, there is meroblastic CLEAVAGE, but where it is absent, or nearly so, cleavage is holoblastic, as in Amphioxus. Yolk is almost absent from mammal eggs, since food is provided directly from the mother, via the PLACENTA.yolk (yōk) One of the types of nutritive material stored in the oocyte (ovum) for the nutrition of the embryo; particularly abundant and conspicuous in birds' eggs. [A.S. geolca;geolu, yellow]yolk
Synonyms for yolknoun the yellow spherical part of an egg that is surrounded by the albumenSynonymsRelated Wordsnoun nutritive material of an ovum stored for the nutrition of an embryo (especially the yellow mass of a bird or reptile egg)SynonymsRelated Words |