Oxford
`
`Collegium v. Purdue, PGR2018-00048
`
`DICTIONARY OF
`
`aMhenna)yeGminienl! aneicee
`WaGraneen eeee
`
`Purdue 2003
`Collegium v. Purdue, PGR2018-00048
`
`

`

`ALRPlLNEARECO
`
`A Dictionary of
`Science
`
`OXFORD
`UNIVERSITY PRESS
`
`Purdue 2003
`Collegium v. Purdue, PGR2018-00048
`
`

`

` peppy LRISSRESCSURSIALOLESOCIOELEOEEIUSEETEI
`
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`Purdue 2003
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`

`LOINIRIE
`
`382
`homeoctic geneseeeprrrreerennesisitiiiimuermmnunernrtuisranertiranuunisniuntutmntmnterentimetnttneNtinnLttttay,
`
`rise to H. heidelbergensis (represented by
`ance and body temperature(see homoio-
`Heidelberg man and Boxgrove man).
`thermy; poikilothermy).
`These hominids lived around 500 000
`homectic genes A class of genes that
`years ago. H. heidelbergensis is thought to
`play a central role in controlling the
`have been the common ancestor of both
`early development and differentiation of
`H. neanderthalensis (*Neanderthal man)
`embryonic tissues in eukaryotic organ-
`and H. sapiens. Both species appeared
`isms. They code for proteins that bind
`about 100 000 years ago. See also Cro-
`DNA and regulate the expression of a
`magnon man.
`wide range of other genes. This binding
`homocyclic See cyclic.
`capability resides in a structural domain
`of the protein called a homeodomain,
`homodont Describing animals whose
`encoded by a nucleotide sequence
`teeth are all of the same type. Most ver-
`(*homeobox)that is characteristic of ho-
`tebrates except mammals are homodont,
`meotic genes. These genes werefirst
`Compare heterodont.
`identified in Drosophila fruit flies,
`homogametic sex The sex thatisde |
`through the occurrence of mutations
`termined by possession of two similar
`|
`that alter the development of entire
`*sex chromosomes(e.g. XX) In humans
`=
`body segments. Drosophila flies have two
`and many other mammalsthis is the fe.
`major clusters of homeotic genes: the an-
`male sex. All the reproductive cells (ga-
`tennapedia complex, which controls de-
`metes) produced by the homogametic sex:
`velopment of the head and anterior
`have the same kind of sex chromosome
`thoracic segments, and the bithorax com-
`(ie, an X chromosome). Compare hetero
`plex, which governs the development of
`gametic sex.
`posterior segments. For example, one
`mutation of the bithorax cluster causes
`homogamy The condition in a flower.;
`the thoracic segment that normally bears
`in which the male and female reproduc, |
`the halteres (balancing organs; see Dip-
`tive organs mature at the sametime,
`|
`tera) to be transformed into a segment
`thereby allowing self-fertilization. Come:
`{
`bearing a pair of wings. In vertebrates
`pare dichogamy.
`i
`there are four clusters of homeotic genes
`homogeneous Relating to only one
`located on separate chromosomes,
`phase, e.g. a homogeneous mixture, a
`hominid Any member of the primate
`homogeneous “catalyst. Compare hetera
`geneous.
`family Hominidae, which includes man
`and his fossil ancestors (fessil hominids) in
`homoiothermy The maintenance by
`the genus *Homo.
`an animalof its internal body tempera-
`ture at a relatively constant value by
`Home The genus of primates that in-
`
`cludes modern man (H.sapiens, the only
`using metabolic processes to counteract
`fluctuations in the temperature of the
`living representative) and various extinct
`environment. Homoiothermy occurs in
`species, The oldest Homo fossils are those
`birds and mammals, which are described
`
`of H. habilis and H. rudolfensis, which first
`as *endotherms. The heat produced by
`appeared in Africa 2.3-2.4 million years
`their tissue metabolism and the heatlost:
`
`ago. Both species used simple stone tools.
`‘to the environment are balanced by varl«
`H. habilis appears to have been 1-15 m
`tall and had more manlike features and a
`ous means to keep body temperature
`
`constant; 36-38°C in mammals and
`larger brain than *Australopithecus, H.
`erectus appeared about 1.9 million years
`38-40°C in birds. The *hypothalamusin
`the brain monitors blood temperature
`ago. Fossils of H. erectus, which was for-
`
`merly called Pithecanthropus (ape man),
`and controls thermoregulation by both
`
`nervous and hormonal means. This pro-
`include Java man and Peking man. They
`are similar to present-day man except
`duces both short-term responses, such as
`
`that there was a prominent ridge above
`shivering or sweating, and long-term ade
`the eyes and no forehead or chin. They
`Justments to metabolism according to:
`used crude stone tools and fire. H. erectus
`
`seasonal changesin climate (acclimatize
`
`
`is thought to have evolved from H. er
`tion), Endotherms generally possess inst
`
`gaster, a species that may also have given
`lating feathers or fur. Their relatively
`
`
`:
`
`
`
`teiansooonncestunSabini08
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`Purdue 2003
`Collegium v. Purdue, PGR2018-00048
`
`