heredity — /heuh red i tee/, n., pl. heredities. Biol. 1. the transmission of genetic characters from parents to offspring: it is dependent upon the segregation and recombination of genes during meiosis and fertilization and results in the genesis of a new… … Universalium
Antibody — Immunoglobulin redirects here. For the immunoglobulin family, see Immunoglobulin superfamily. Antibodies redirects here. For the film, see Antibodies (film). Each antibody binds to a specific antigen; an interaction similar to a lock and key. An… … Wikipedia
Immunoglobulin class switching — Mechanism of class switch recombination that allows isotype switching in activated B cells Immunoglobulin class switching (or isotype switching or isotypic commutation or class switch recombination(CSR)) is a biological mechanism that changes a B … Wikipedia
nebula — nebular, adj. /neb yeuh leuh/, n., pl. nebulae / lee , luy /, nebulas. 1. Astron. a. Also called diffuse nebula. a cloud of interstellar gas and dust. Cf. dark nebula, emission nebula, reflection nebula … Universalium
plant — plantable, adj. plantless, adj. plantlike, adj. /plant, plahnt/, n. 1. any member of the kingdom Plantae, comprising multicellular organisms that typically produce their own food from inorganic matter by the process of photosynthesis and that… … Universalium
GENETIC ANCESTRY, JEWISH — Background The human genome refers to approximately three billion chemical letters (nucleotides) comprising the sequence of deoxyribonucleic acid (DNA) in almost every cell of each human being. There are four different nucleotides (adenine,… … Encyclopedia of Judaism
Strömgren sphere — In theoretical astrophysics, a Strömgren sphere is the sphere of ionized hydrogen (H II) around a young star of the spectral classes O or B. Its counterpart in the real word are the H II regions, a type of an emission nebula, the most prominent… … Wikipedia
nucleic acid — /nooh klee ik, klay , nyooh /, Biochem. any of a group of long, linear macromolecules, either DNA or various types of RNA, that carry genetic information directing all cellular functions: composed of linked nucleotides. [1890 95; NUCLE(US) + IC;… … Universalium
evolution — evolutional, adj. evolutionally, adv. /ev euh looh sheuhn/ or, esp. Brit., /ee veuh /, n. 1. any process of formation or growth; development: the evolution of a language; the evolution of the airplane. 2. a product of such development; something… … Universalium
Evolution of sexual reproduction — The evolution of sexual reproduction is currently described by several competing scientific hypotheses. All sexually reproducing organisms derive from a common ancestor which was a single celled eukaryotic species[1]. Many protists reproduce… … Wikipedia
DNA repair — For the journal, see DNA Repair (journal). DNA damage resulting in multiple broken chromosomes DNA repair refers to a collection of processes by which a cell identifies and corrects damage to the DNA molecules that encode its genome. In human… … Wikipedia