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Tribolium Castaneum (Herbst, 1797) (32875109665)
The red flour beetle (''Tribolium castaneum'') is a species of beetle in the family Tenebrionidae, the darkling beetles. The red flour beetle, and other closely related beetles like ''Gnatocerus cornutus'', are a worldwide pest of stored products, particularly food grains, and a model organism for ethological and food safety research. Description Adult beetles are small, around 3–4 mm long (1/8 inches), of a uniform rust, brown or black color. Head and pronotum are sometimes darker than rest of body. Ecology The red flour beetle attacks stored grain and other food products including flour, cereals, pasta, biscuits, beans, and nuts, causing loss and damage. The United Nations, in a recent post-harvest compendium, estimated that ''Tribolium castaneum'' and ''Tribolium confusum'', the confused flour beetle, are "the two most common secondary pests of all plant commodities in store throughout the world." A research on hermetic storage of wheat and maize flour protects again ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johann Friedrich Wilhelm Herbst
Johann Friedrich Wilhelm Herbst (1 November 1743 – 5 November 1807) was a German natural history, naturalist and entomologist from Petershagen, Minden-Ravensberg. He served as a chaplain in the Prussian army. His marriage in Berlin, 1770, with Euphrosyne Luise Sophie (1742–1805), daughter of the Prussian ''Hofrat'' Libert Waldschmidt, seems to have been childless. He was the joint editor, with Carl Gustav Jablonsky, of ''Naturgeschichte der in- und ausländischen Insekten'' (1785–1806, 10 volumes), which was one of the first attempts at a complete survey of the order Coleoptera. Herbst's ''Naturgeschichte der Krabben und Krebse'', released in installments, was the first full survey of crustaceans. Herbst's other works included ''Anleitung zur Kenntnis der Insekten'' (1784–86, 3 volumes), ''Naturgeschichte de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pheromones
A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavior of the receiving individuals. There are '' alarm pheromones'', ''food trail pheromones'', '' sex pheromones'', and many others that affect behavior or physiology. Pheromones are used by many organisms, from basic unicellular prokaryotes to complex multicellular eukaryotes. Their use among insects has been particularly well documented. In addition, some vertebrates, plants and ciliates communicate by using pheromones. The ecological functions and evolution of pheromones are a major topic of research in the field of chemical ecology. Background The portmanteau word "pheromone" was coined by Peter Karlson and Martin Lüscher in 1959, based on the Greek () and (). Pheromones are also sometimes classified as ecto-hormones ("ecto-" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MRNA
In molecular biology, messenger ribonucleic acid (mRNA) is a single-stranded molecule of RNA that corresponds to the genetic sequence of a gene, and is read by a ribosome in the process of Protein biosynthesis, synthesizing a protein. mRNA is created during the process of Transcription (biology), transcription, where an enzyme (RNA polymerase) converts the gene into primary transcript mRNA (also known as pre-mRNA). This pre-mRNA usually still contains introns, regions that will not go on to code for the final amino acid sequence. These are removed in the process of RNA splicing, leaving only exons, regions that will encode the protein. This exon sequence constitutes mature mRNA. Mature mRNA is then read by the ribosome, and the ribosome creates the protein utilizing amino acids carried by transfer RNA (tRNA). This process is known as Translation (biology), translation. All of these processes form part of the central dogma of molecular biology, which describes the flow of geneti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RNA Interference
RNA interference (RNAi) is a biological process in which RNA molecules are involved in sequence-specific suppression of gene expression by double-stranded RNA, through translational or transcriptional repression. Historically, RNAi was known by other names, including ''co-suppression'', ''post-transcriptional gene silencing'' (PTGS), and ''quelling''. The detailed study of each of these seemingly different processes elucidated that the identity of these phenomena were all actually RNAi. Andrew Fire and Craig Mello shared the 2006 Nobel Prize in Physiology or Medicine for their work on RNAi in the nematode worm ''Caenorhabditis elegans'', which they published in 1998. Since the discovery of RNAi and its regulatory potentials, it has become evident that RNAi has immense potential in suppression of desired genes. RNAi is now known as precise, efficient, stable and better than antisense therapy for gene suppression. Antisense RNA produced intracellularly by an expression vector may be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bicoid (gene)
Homeotic protein bicoid is encoded by the ''bcd'' maternal effect gene in ''Drosophilia''. Homeotic protein bicoid concentration gradient patterns the Drosophila_embryogenesis#Anterior-posterior_axis_patterning_in_Drosophila, anterior-posterior (A-P) axis during Drosophila embryogenesis, ''Drosophila'' embryogenesis. Bicoid was the first protein demonstrated to act as a morphogen. Although bicoid is important for the development of ''Drosophila'' and other higher dipterans, it is absent from most other insects, where its role is accomplished by other genes. Role in axial patterning ''Bicoid'' mRNA is actively localized to the anterior of the fruit fly egg during oogenesis along microtubules by the motor protein dynein, and retained there through association with Cell cortex, cortical actin. Translation of ''bicoid'' is regulated by its Bicoid 3′-UTR regulatory element, 3′ UTR and begins after egg deposition. Diffusion and convection within the syncytium produce an exponenti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drosophila
''Drosophila'' (), from Ancient Greek δρόσος (''drósos''), meaning "dew", and φίλος (''phílos''), meaning "loving", is a genus of fly, belonging to the family Drosophilidae, whose members are often called "small fruit flies" or pomace flies, vinegar flies, or wine flies, a reference to the characteristic of many species to linger around overripe or rotting fruit. They should not be confused with the Tephritidae, a related family, which are also called fruit flies (sometimes referred to as "true fruit flies"); tephritids feed primarily on unripe or ripe fruit, with many species being regarded as destructive agricultural pests, especially the Mediterranean fruit fly. One species of ''Drosophila'' in particular, ''Drosophila melanogaster'', has been heavily used in research in genetics and is a common model organism in developmental biology. The terms "fruit fly" and "''Drosophila''" are often used synonymously with ''D. melanogaster'' in modern biological literatur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inbreeding Depression
Inbreeding depression is the reduced biological fitness caused by loss of genetic diversity as a consequence of inbreeding, the breeding of individuals closely related genetically. This loss of genetic diversity results from small population size, often stemming from a population bottleneck. Biological fitness refers to an organism's ability to survive and perpetuate its genetic material. In general, the higher the genetic variation or gene pool within a breeding population, the less likely it is to suffer from inbreeding depression, though inbreeding and outbreeding depression can simultaneously occur. Inbreeding depression seems to be present in most populations of organisms, but varies across mating systems. Remarkably, hermaphroditic species often exhibit lower degrees of inbreeding depression than outcrossing species, as repeated generations of selfing is thought to purge deleterious alleles from populations. For example, the outcrossing nematode (roundworm) '' Caen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Incompatibility
Genetic incompatibility describes the process by which mating yields offspring that are nonviable, prone to disease, or genetically defective in some way. In nature, animals can ill afford to devote costly resources for little or no reward, ergo, mating strategies have evolved to allow females to choose or otherwise determine mates which are more likely to result in viable offspring. Polyandry in animals, Polyandry, for instance, when a female mates with two or more males during a period of sexual receptivity, reduces the chance that a singular mate is genetically incompatible. Exactly how females determine compatible genes prior to mating is not completely understood, but various mechanisms have been proposed, such as pheromones and male appearance and/or courtship behavior. It is also surmised that sexual selection can continue after copulation, the so called 'cryptic female choice', so named because it takes place within the body and cannot be directly observed. In this scenari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polygyny In Animals
Polygyny (; from Neo-Greek , ) is a mating system in which one male lives and mates with multiple females but each female only mates with a single male. Systems where several females mate with several males are defined either as promiscuity or polygynandry. Lek mating is frequently regarded as a form of polygyny, because one male mates with many females, but lek-based mating systems differ in that the male has no attachment to the females with whom he mates, and that mating females lack attachment to one another.Clutton-Brock T.H. (1989). ‘Review lecture: mammalian mating systems.' ''Proceedings of the Royal Society of London''. Series B, Biological Sciences 236: 339–372. Polygyny is typical of one-male, multi-female groupsBoyd, R., & Silk, J. B. (2009). How Humans Evolved (preferably the downloadable pdf version): WW Norton & Company, New York. and can be found in many species including: elephant seal, spotted hyena, gorilla, red-winged prinia, house wren, hamadryas bab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal Sexual Behaviour
Animal sexual behaviour takes many different forms, including within the same species. Common mating or Reproduction, reproductively motivated systems include Monogamous pairing in animals, monogamy, Polygyny in animals, polygyny, Polyandry in nature, polyandry, Animal sexual behaviour#Polygamy, polygamy and Promiscuity#Other animals, promiscuity. Other sexual behaviour may be reproductively motivated (e.g. Sexual coercion among animals, sex apparently due to duress or coercion and situational sexual behaviour) or Non-reproductive sexual behavior in animals, non-reproductively motivated (e.g. Homosexual behavior in animals, homosexual sexual behaviour, bisexuality, bisexual sexual behaviour, cross-species sex, Paraphilia, sexual arousal from objects or places, Necrophilia in animals, sex with dead animals, etc.). When animal sexual behaviour is reproductively motivated, it is often termed ''mating'' or ''Copulation (zoology), copulation''; for most non-human mammals, mating and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mutation
In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, mitosis, or meiosis or other types of damage to DNA (such as pyrimidine dimers caused by exposure to ultraviolet radiation), which then may undergo error-prone repair (especially microhomology-mediated end joining), cause an error during other forms of repair, or cause an error during replication ( translesion synthesis). Mutations may also result from substitution, insertion or deletion of segments of DNA due to mobile genetic elements. Mutations may or may not produce detectable changes in the observable characteristics ( phenotype) of an organism. Mutations play a part in both normal and abnormal biological processes including: evolution, cancer, and the development of the immune system, including junctional diversity. Mutati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
