|
ulna: The bone of the
lower arm that hinges at the elbow with the humerus.
uniface: A flake tool
modified on either the dorsal or ventral side only.
uniformitarianism:
Originally a concept in geology, the precept that the processes
observable in the present can also be used to explain the past.
uniparental inheritance:
A phenomenon, usually exhibited by extracellular genes, in which
all progeny have the phenotype of only one parent.
unique (single-copy)
sequences: A class of DNA sequences that has only one to a few copies
per genome.
unlineal: Patrilineal
(agnatic) or matrilineal (uterine) descent.
upstream activator
sequences (UASs): In yeast, elements that are functionally similar
to enhancers in other eukaryotes. UASs can function in either orientation
and at variable distances upstream of the promoter.
uracil (U): A pyrimidine
base found in RNA but not in DNA. In double-stranded RNA it pairs
with adenine.
uranium series dating:
A dating method based on the radioactive decay of isotopes of uranium.
It has proved particularly useful for the period before 50,000 years
ago, which lies outside the time range of radiocarbon dating.
uterine: See matrilineal.
uxorilocal: Residence
of a married couple with the wife's kin (formally called "matrilocal").
|
