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Candling
Candling is a method used in embryology to study the growth and development of an embryo inside an egg. The method uses a bright light source behind the egg to show details through the shell, and is so called because the original sources of light used were candles. The technique of using light to examine eggs is used in the egg industry to assess the quality of edible eggs. In Plants This technique can also be used to assess the quality and development stage of certain translucent plant seeds, especially those of Lilies and their close relatives. Ripe, viable seeds have a visible embryo within them when viewed in transmitted light, so good seeds can be sorted out from the non-viable seeds and chaff, if desired. Candling is a highly useful method with certain species that germinate erratically or very slowly, as seed germination causes the embryo to enlarge. Candling can thus be used to estimate the optimal time for planting seeds that are being stratified. Care must be take ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CDC Microbiologist Demonstrating How To Candle An Embryonated Chicken Egg
The Centers for Disease Control and Prevention (CDC) is the national public health agency of the United States. It is a United States federal agency, under the Department of Health and Human Services, and is headquartered in Atlanta, Georgia. The agency's main goal is the protection of public health and safety through the control and prevention of disease, injury, and disability in the US and worldwide. The CDC focuses national attention on developing and applying disease control and prevention. It especially focuses its attention on infectious disease, food borne pathogens, environmental health, occupational safety and health, health promotion, injury prevention and educational activities designed to improve the health of United States citizens. The CDC also conducts research and provides information on non-infectious diseases, such as obesity and diabetes, and is a founding member of the International Association of National Public Health Institutes. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embryology
Embryology (from Greek ἔμβρυον, ''embryon'', "the unborn, embryo"; and -λογία, '' -logia'') is the branch of animal biology that studies the prenatal development of gametes (sex cells), fertilization, and development of embryos and fetuses. Additionally, embryology encompasses the study of congenital disorders that occur before birth, known as teratology. Early embryology was proposed by Marcello Malpighi, and known as preformationism, the theory that organisms develop from pre-existing miniature versions of themselves. Aristotle proposed the theory that is now accepted, epigenesis. Epigenesis is the idea that organisms develop from seed or egg in a sequence of steps. Modern embryology, developed from the work of Karl Ernst von Baer, though accurate observations had been made in Italy by anatomists such as Aldrovandi and Leonardo da Vinci in the Renaissance. Comparative embryology Preformationism and epigenesis As recently as the 18th century, the prevailin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embryo
An embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sperm cell. The resulting fusion of these two cells produces a single-celled zygote that undergoes many cell divisions that produce cells known as blastomeres. The blastomeres are arranged as a solid ball that when reaching a certain size, called a morula, takes in fluid to create a cavity called a blastocoel. The structure is then termed a blastula, or a blastocyst in mammals. The mammalian blastocyst hatches before implantating into the endometrial lining of the womb. Once implanted the embryo will continue its development through the next stages of gastrulation, neurulation, and organogenesis. Gastrulation is the formation of the three germ layers that will form all of the different parts of the body. Neurulation forms the nervous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Egg (biology)
An egg is an organic vessel grown by an animal to carry a possibly fertilized egg cell (a zygote) and to incubate from it an embryo within the egg until the embryo has become an animal fetus that can survive on its own, at which point the animal hatches. Most arthropods such as insects, vertebrates (excluding live-bearing mammals), and mollusks lay eggs, although some, such as scorpions, do not. Reptile eggs, bird eggs, and monotreme eggs are laid out of water and are surrounded by a protective shell, either flexible or inflexible. Eggs laid on land or in nests are usually kept within a warm and favorable temperature range while the embryo grows. When the embryo is adequately developed it hatches, i.e., breaks out of the egg's shell. Some embryos have a temporary egg tooth they use to crack, pip, or break the eggshell or covering. The largest recorded egg is from a whale shark and was in size. Whale shark eggs typically hatch within the mother. At and up to , the o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Candle
A candle is an ignitable wick embedded in wax, or another flammable solid substance such as tallow, that provides light, and in some cases, a fragrance. A candle can also provide heat or a method of keeping time. A person who makes candles is traditionally known as a chandler. Various devices have been invented to hold candles, from simple tabletop candlesticks, also known as candle holders, to elaborate candelabra and chandeliers. For a candle to burn, a heat source (commonly a naked flame from a match or lighter) is used to light the candle's wick, which melts and vaporizes a small amount of fuel (the wax). Once vaporized, the fuel combines with oxygen in the atmosphere to ignite and form a constant flame. This flame provides sufficient heat to keep the candle burning via a self-sustaining chain of events: the heat of the flame melts the top of the mass of solid fuel; the liquefied fuel then moves upward through the wick via capillary action; the liquefied fuel finally ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Illinois System
The University of Illinois System is a system of public universities in Illinois consisting of three universities: Chicago, Springfield, and Urbana-Champaign. Across its three universities, the University of Illinois System enrolls more than 94,000 students. It had an operating budget of $7.18 billion in 2021. Organization The University of Illinois System of universities comprises three universities in the U.S. state of Illinois: Urbana-Champaign, Chicago, and Springfield. The university in Urbana-Champaign is known as "Illinois", "U of I", or "UIUC", whereas the Chicago campus is known as "UIC" and the Springfield campus as "UIS". The system is governed by a board of trustees consisting of thirteen members: the governor of Illinois serves as an ex officio member, nine trustees are appointed by the governor of Illinois, and a student trustee elected by referendum represents each of the system's three universities. One of the three student trustees is designated by the g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pehr Hilleström-Äggprovet
Pehr is a predominantly Swedish language masculine give name and may refer to: *Pehr Adlerfelt (1680–1743), Swedish Army colonel *Pehr von Afzelius (1760–1843), Swedish medical doctor and professor * Pehr Victor Edman (1916—1977), Swedish biochemist * Pehr von Ehrenheim (1823–1918), Swedish politician *Pehr Forsskål (also known as Peter Forsskål; 1732–1763), Swedish-Finnish explorer, orientalist and naturalist * Pehr Götrek (1798–1876), Swedish Christian communist *Pehr Gyllenhammar (1901–1988), Swedish businessman *Pehr G. Gyllenhammar (born 1935), Swedish businessman * Pehr Harbury (born 1965), American biochemist * Pehr Hilleström (1732–1816), Swedish artist * Pehr Ferdinand Holm (1844–1917), Swedish-born New Zealand mariner *Pehr G. Holmes (1881–1952), Swedish-born American politician *Pehr Hörberg (1746–1816), Swedish painter and musician *Pehr Janse (1893–1961), Swedish Army major general *Pehr Kalm (1716–1779), Finnish explorer and naturali ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seed
A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiosperm plants. Seeds are the product of the ripened ovule, after the embryo sac is fertilized by sperm from pollen, forming a zygote. The embryo within a seed develops from the zygote, and grows within the mother plant to a certain size before growth is halted. The seed coat arises from the integuments of the ovule. Seeds have been an important development in the reproduction and success of vegetable gymnosperm and angiosperm plants, relative to more primitive plants such as ferns, mosses and liverworts, which do not have seeds and use water-dependent means to propagate themselves. Seed plants now dominate biological niches on land, from forests to grasslands both in hot and cold climates. The term "seed" also has a general me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lilium
''Lilium'' () is a genus of herbaceous flowering plants growing from bulbs, all with large prominent flowers. They are the true lilies. Lilies are a group of flowering plants which are important in culture and literature in much of the world. Most species are native to the northern hemisphere and their range is temperate climates and extends into the subtropics. Many other plants have "lily" in their common names, but do not belong to the same genus and are therefore not true lilies. Description Lilies are tall perennials ranging in height from . They form naked or tunicless scaly underground bulbs which are their organs of perennation. In some North American species the base of the bulb develops into rhizomes, on which numerous small bulbs are found. Some species develop stolons. Most bulbs are buried deep in the ground, but a few species form bulbs near the soil surface. Many species form stem-roots. With these, the bulb grows naturally at some depth in the soil, and each ye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lily Seed Germination Types
Lilies seed germination is classified as either epigeal or hypogeal. These classifications may be further refined as immediate or delayed. Whether a lily is epigeal or hypogeal may be related to survival strategies developed according to the climate where the lily originated. Epigeal lilies evolved in moderate climates. Hypogeal lilies evolved in harsher habitats where it would be advantageous to store food in a bulb, and later send up leaves in the spring. Epigeal Lilies Asiatic lilies include species of ''Lilium lancifolium'' (syn.tigrinum), ''L. cernuum'', ''L. davidii'', ''L. maximowiczii'', ''L. macultum'', ''L. hollandicum'', ''L. amabile'', ''L. pumilum'', ''L. concolor'', and ''L. bulbiferum''. Epigeal trumpet lily species are ''L. leucanthum'', ''L. ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratification (botany)
In horticulture, stratification is a process of treating seeds to simulate natural conditions that the seeds must experience before germination can occur. Many seed species have an embryonic dormancy phase, and generally will not sprout until this dormancy is broken. The term stratification can be traced back to at least 1664 in ''Sylva, or A Discourse of Forest-Trees and the Propagation of Timber'', where seeds were layered (stratified) between layers of moist soil and exposing these strata to winter conditions. Thus, stratification became the process by which seeds were artificially exposed to conditions to encourage subsequent germination. Cold stratification Cold stratification is the process of subjecting seeds to both cold and moist conditions. Seeds of many trees, shrubs and perennials require these conditions before germination will ensue. In the wild In the wild, seed dormancy is usually overcome by the seed spending time in the ground through a winter period and havi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lutherie
A luthier ( ; AmE also ) is a craftsperson who builds or repairs string instruments that have a neck and a sound box. The word "luthier" is originally French and comes from the French word for lute. The term was originally used for makers of lutes, but it came to be used already in French for makers of most bowed and plucked stringed instruments such as members of the violin family (including violas, cellos, and double basses) and guitars. Luthiers, however, do not make harps or pianos; these require different skills and construction methods because their strings are secured to a frame. The craft of luthiers, lutherie (rarely called "luthiery", but this often refers to stringed instruments other than those in the violin family), is commonly divided into the two main categories of makers of stringed instruments that are plucked or strummed and makers of stringed instruments that are bowed. Since bowed instruments require a bow, the second category includes a subtype known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
