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Response written by: Elphège Nora, PhD - postdoctoral researcher in Edith Heard's laboratory, Institut Curie
Each cell of the body produces molecules known as proteins. The structure of proteins...
Read more...Response written by: Elphège Nora, PhD - postdoctoral researcher in Edith Heard's laboratory, Institut Curie
Germ cells of human beings (and all other organism actually) are unfortunately unable...
Read more...| Term | Definition |
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| Natural variation |
Similar to genetic variation it refers to the variation in the genetic and epigenetic material of a population or species, and includes the nuclear, mitochodrial, ribosomal genomes as well as the genomes of other organelles. New genetic variation is caused by epigenetic or genetic mutation. It may end up in take the form of recombination, migration and/or alterations in the karyotype (the number, shape, size and internal arrangement of the chromosomes). Genetic drift is a statistical measure of the rate of genetic variation in a population.
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| Nicotinamide |
(Niacinamide) The amide of niacine, also known as vitamin B3, found in meat, eggs, poultry, leafy green vegetables, etc. Used to derive the co-enzyme nicotinamide adenine dinucleotide (NAD) or its phosphate NADP. It is a major component of the biochemical pathway of respiration.
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| Non-coding RNA |
ncRNA is transcribed from DNA, but not translated into protein. It often plays a regulatory role. Some probably most ancient ncRNAs encompass catalytic functions and are called ribozymes (e.g. RNaseP). Others are tRNAs and ribonucleoprotein complexes such as rRNA within ribosomes or snRNPs of spliceosomes. Others function as RNA templates within telomerase which is related to reverse transcriptase.
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| Non-Mendelian inheritance |
Deviation from Mendel's rules. Mendel's experiments established three basic genetic rules: 1. Some alleles are dominant, others recessive. 2. During gamete formation different alleles segregate from each other. 3. Different genes assort independently. Imprinting is an exception to Mendel's rules because the behavior of imprinted genes is affected by which parent the genes are inherited from.
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| Nucleic acid |
A complex, high-molecular-weight biochemical macromolecule composed of nucleotide chains that convey genetic information. The most common nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Nucleic acids are found in all living cells and viruses.
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| Nucleosome |
The fundamental repeating subunit of eukayotic DNA, and is made up of DNA and histone proteins.
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| Nucleus |
The organelle-compartment of a eukaryotic cell that contains DNA organized into chromosomes; separated from the cytoplasm by double membrane perforated by nuclear pores.
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