Barr body
A dense object lying along the inside of the nuclear envelope in female mammalian cells,
representing an inactivated X chromosome.
Basal
Located at or near the base of a plant stem, or at the base of any other plant part.
Basal body
A eukaryotic cell organelle consisting of a 9 + 0 arrangement of microtubule triplets; may
organize the microtubule assembly of a cilium or flagellum; structurally identical to a
centriole.
Basal metabolic rate (BMR)
The minimal number of kilocalories a resting animal requires to fuel itself for a given time.
Base
A substance that reduces the hydrogen ion concentration in a solution.
Basement membrane
The floor of an epithelial membrane on which the basal cells rest.
Base-pair substitution
A point mutation; the replacement of one nucleotide and its partner from the
complementary DNA strand by another pair of nucleotides.
Base-pairing principle
In the formation of nucleic acids, the requirement that adenine must always pair with
thymine (or uracil) and guanine with cytosine.
Basidium
A reproductive appendage that produces sexual spores on the gills of mushrooms. The
fungal division Basidiomycota is named for this structure.
Basifixed
Attached by the base, as certain anthers are to their filaments.
Batesian mimicry
A type of mimicry in which a harmless species looks like a different species that is poisonous
or otherwise harmful to predators.
Behavior
All of the acts an organism performs, as in, for example, seeking a suitable habitat, obtaining
food, avoiding predators, and seeking a mate and reproducing.
ff
(ff)
#1