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Dysgenics

Dysgenics is the belief that peoples genes may get worse over the course of generations. The adjective "dysgenics" is the antonym of "eugenics". It was first used about 1915 by David Starr Jordan. He thought there might be dysgenic effects in Wor ...

FOXP2

FOXP2 is a gene which codes for a protein needed for speech and language. It codes for "Forkhead box protein P2", which is needed for the proper development of speech and language in humans. Versions of this gene occur in many vertebrates, where ...

Gene family

A gene family is a set of several similar genes. They occur by the duplication of a single original gene. Usually they have similar biochemical functions. The idea that genes get duplicated is almost as old as the science of genetics. One such fa ...

Genes, Brain and Behavior

Genes, Brain and Behavior is a peer-reviewed scientific journal covering the fields of the genetics of behavior, the nervous system, and mental illness. It began in 2002. It is the official journal of the International Behavioural and Neural Gene ...

Genome

The genome of an organism is the whole of its hereditary information encoded in its DNA. This includes both the genes and the non-coding sequences of the DNA. Professor Hans Winkler coined the term in 1920. Winklers definition, in translation, ru ...

Genomics

Genomics is the part of genetics which studies the genomes of organisms. This includes the entire DNA sequence of organisms and fine-scale genetic mapping. The field also includes studies of genes working together. Examples are heterosis, epistas ...

Haplotype

A haplotype is a term in genetics. It is short for haploid genotype. A haplotype is a collection of specific alleles in a cluster of tightly-linked genes on a chromosome. A cluster is usually inherited together. Put simply, haplotype is a closely ...

HUGO Gene Nomenclature Committee

The HUGO Gene Nomenclature Committee sets a unique and meaningful name for every known human gene. It asks experts their opinions. The HGNC gives a long name, and an abbreviation to every gene. The HGNC is part of the Human Genome Organisation. T ...

Hybrid vigour

Hybrid vigour is the improved activity and survival of hybrid offspring. The technical term in genetics is heterosis. Inbreeding in a normal population leads to the offspring getting worse, less fit, less fertile and usually not living as long as ...

Luria–Delbruck experiment

The Luria–Delbruck experiment, 1943, also called the Fluctuation Test, asks the question: are mutations independent of natural selection? Or are they directed by the selection? Max Delbruck and Salvador Luria showed that in bacteria, DNA mutation ...

RNA splicing

RNA splicing is a stage in gene transcription. Messenger RNA, which transfers the code from DNA to proteins, is built in two stages. In the first stage, each gene is translated into a pre-mRNA. Then the exons in pre-mRNAs are joined by splicing, ...

Single nucleotide polymorphism

A single nucleotide polymorphism is a DNA sequence variation in a population. A SNP is just a single nucleotide difference in the genome. For example, sequenced DNA fragments from two people, AAGC C TA to AAGC T TA, is different in a single nucle ...

Transcription factor

Transcription factors help to regulate genes. Each transcription factor binds to a specific DNA sequence. That is how they control the rate of transcription of genetic information from DNA to messenger RNA. A transcription factor is sometimes cal ...

Dinosaur renaissance

Dinosaur renaissance is a term coined in a 1975 issue of Scientific American by Robert Bakker to describe the renewed interest in paleontology. This has lasted from the 1970s to the present. It was caused by a great increase in dinosaur discoveri ...

Evolutionary arms race

An evolutionary arms race is when two species are so linked that a change in one indirectly causes a change in the other. It is a metaphor drawn from the so-called arms race between the West and the Soviet Union, after the second world war. Evolu ...

Natural selection

Natural selection is a central concept of evolution. The English biologist Charles Darwin and Alfred Russel Wallace, and is sometimes called the survival of the fittest. Darwin chose the name as an analogy with artificial selection. Natural selec ...

Watchmaker analogy

The Watchmaker analogy is a teleological argument. In simple terms, it states that because there is a design, there must be a designer. The analogy is important in natural theology where it is used to show the existence of God as well as supporti ...

Antimicrobial

An antimicrobial is an agent that kills microorganisms or stops their growth. Antimicrobial medicines can be grouped according to the microorganisms they act primarily against. For example, antibiotics are used against bacteria, and antifungals a ...

Biofilm

A biofilm is any group of microorganisms which stick to cell surfaces. These sticky cells create a slimy layer outside the cells of the body. The cells in the biofilm produce extracellular polysaccharides, proteins, lipids and DNA. Because they h ...

Enterotype

An enterotype is a classification of gut flora. It is based on the ecosystem in the human intestinal system. The classification is done by identifying the bacteria and protists which live there. This is called the "human gut biome". Research show ...

Gut flora

Gut flora consists of microorganisms that live in the digestive system of animals. It is the largest reservoir of microbes in the human microbiome. The human body, consisting of about 100 trillion cells, carries about ten times as many microorgan ...

Horizontal gene transfer

Horizontal gene transfer is any process in which an organism gets genetic material from another organism without being the offspring of that organism. By contrast, vertical transfer occurs when an organism gets genetic material from its ancestor, ...

Infection

Infection is the invasion of an organisms body tissues by disease-causing agents. The disease is caused by the invading agents multiplying. As they multiply, they produce toxins and damage host tissues. Infectious disease, also known as transmiss ...

Restriction enzyme

A restriction enzyme is an enzyme that cuts DNA at particular places. It works at or near specific recognition nucleotide sequences known as "restriction sites". To cut DNA, all restriction enzymes make two incisions, once through each strand of ...

Anfinsens dogma

Anfinsens dogma is a hypothesis in molecular biology suggested by Christian Anfinsen. The idea is that a protein folding into its native structure is done automatically by the proteins amino acid sequence. It is only true for some proteins. For o ...

Central dogma of molecular biology

The central dogma of molecular biology is a phrase by Francis Crick, who proposed the double helix structure of DNA. It means that information passes from DNA to proteins via RNA, but proteins cannot pass the information back to DNA. Crick first ...

Chaperone (protein)

A molecular chaperone is a proteins which helps large molecules fold or unfold. Some help assemble or take apart other macromolecular structures. They do not occur in these structures when the structures go about their normal functions. The first ...

Complementarity (molecular biology)

In molecular biology, complementarity is a property of nucleic acids such as DNA and RNA. Each nucleotide has a nitrogenous base, and each nitrogenous base can pair up with the nitrogenous base from another different nucleotide. One can say that ...

Gene knockout

A gene knockout is a genetic technique in which one of an organisms genes is switched off or replaced by one which does not work. The organisms, such as knockout mice, are used to learn about a gene that has been sequenced, but whose function is ...

Laboratory of Molecular Biology

The Medical Research Council Laboratory of Molecular Biology is a research institute in Cambridge, England. It was involved in the revolution in molecular biology which occurred in the 1950–60s. It is a major medical research laboratory with a br ...

Membrane protein

A membrane protein is a protein molecule that is attached to, or associated with the membrane of a cell or an organelle. 20–30% of all genes in genomes code for membrane proteins. They are targets of over 50% of all modern medicinal drugs.

Meselson–Stahl experiment

The Meselson–Stahl experiment was an experiment done by Matthew Meselson and Franklin Stahl in 1958, using E. coli DNA. With their experiment, they found that DNA replication was semiconservative. The DNA consists of two helices that are combined ...

Nucleosome

Nucleosomes are the building blocks which make up chromosomes. They consist of a segment of DNA wound around a histone protein core. First, DNA and a protein make up chromatin. Then the chromatin is packed up into nucleosomes. Nucleosomes are the ...

Protein

Proteins are long-chain molecules built from small units known as amino acids. They are joined together with peptide bonds. They are biochemical compounds consisting of one or more polypeptides folded into a round or fibrous shape. A polypeptide ...

Protein structure

Protein structure describes how protein molecules are organised. This structure is what makes proteins work. Proteins are important biological macromolecules present in all organisms. They are polymers formed from 20 possible amino acids by RNA t ...

RNA polymerase

RNA polymerase is the enzyme which does transcription.The 2006 Nobel Prize in Chemistry was awarded to Roger D. Kornberg for creating detailed molecular images of RNA polymerase during various stages of the transcription process. With the help of ...

SnRNP

Small nuclear RNA, joins with proteins to form spliceosomes. The spliceosomes govern alternative splicing. The background to this is that, in eukaryotes, most genes code for a protein in separated strings of DNA. This is because, of a total gene, ...

Telomere

A telomere is a region of DNA at the end of a chromosome. It protects the end of the chromosome from deteriorating or fusing with other chromosomes. The telomeres are made of repeated sequences of DNA repetitive DNA. During cell division, enzymes ...

Neuroscience

Neuroscience is the scientific study of the nervous system. It is the branch of biology that investigates the molecular, cellular, developmental, functional, evolutionary, computational, psychosocial and medical aspects of the brain. The nervous ...

Lateral inhibition

In neurobiology, lateral inhibition is the ability of an excited neuron to reduce the activity of its neighbors. It stops action potentials from spreading in the lateral direction. It is called lateral inhibition as it stops neighboring neurons f ...

Neurotransmitter

Neurotransmitters are chemical messengers. They send information between neurons by crossing a synapse. Electrical signals are not able to cross the gap between most neurons. They are changed into chemical signals to cross the gap. Neurotransmitt ...

Thalamus

The thalamus is a midline symmetrical structure in the brains of vertebrates. It is between the cerebral cortex and midbrain. It relays sensory and motor signals to the cerebral cortex, and regulates consciousness, sleep, and alertness. The thala ...

Ammonite

Ammonites were marine cephalopod molluscs of the subclass Ammonoidea. Their widely-known fossils show a ribbed spiral-form shell, in the end compartment of which lived the tentacled animal. These creatures lived in the seas from at least 400 to 6 ...

Fossil

A fossil is the remains or trace of an ancient living thing. Fossils of animals, plants, or protists occur in sedimentary rock. In a typical fossil, the body form is retained, but the original molecules that made up the body have been replaced by ...

Ichnology

Ichnology is the study of trace fossils of once-living things. Burrows, trackways, trails and borings are all examples of traces made by organisms. Scientists study traces made by plants and animals to try to determine their behavior. An ichnolog ...

Lagerstatte

Lagerstatte is a German word for places of exceptional fossil preservation. Adolf Seilacher coined the term in 1970 to describe sites, like Solnhofen, which yielded the most exceptional fossils. Extra-special sites are called Konservat-Lagerstatt ...

Lazarus taxon

In paleontology, a Lazarus taxon is a taxon that disappears from one or more periods of the fossil record, only to appear again later. The term refers to the Gospel of John, in which Jesus is claimed to have raised Lazarus from the dead. Lazarus ...

Mammal-like reptile

Mammal-like reptile is an old term for the therapsids: those synapsids which gave rise to the true mammals. The term is both outmoded and a mistake, because mammals did not descend from reptiles. Both groups descended from early amniotes egg-layi ...

Micropaleontology

Micropaleontology is the branch of paleontology that studies microfossils. Microfossils are fossils generally not larger than four millimeters, and commonly smaller than one millimeter. A microscope is used to study them. Every kingdom of organis ...

Permineralization

Permineralization is a process of fossilization in which mineral deposits form internal casts of organisms. Minerals in water fill the spaces inside organic tissue. The process gives a record of soft tissue as well as hard tissues. Fossils with p ...

Encyclopedic dictionary

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Pino - logical board game which is based on tactics and strategy. In general this is a remix of chess, checkers and corners. The game develops imagination, concentration, teaches how to solve tasks, plan their own actions and of course to think logically. It does not matter how much pieces you have, the main thing is how they are placement!

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