Deoxyribose
The sugar component of DNA, having one less hydroxyl group than ribose, the sugar
component of RNA.
Dependent variable
In an experiment, the dependent variable is the factor that responds when another factor is
manipulated.
Deploblastic
Derived from two embryonic germs layers, the ectoderm and endoderm. Used of lower
invertebrates, such as sponges and coelenterates.
Depolarization
An electrical state in an excitable cell whereby the inside of the cell is made less negative
relative to the outside than at the resting membrane potential. A neuron membrane is
depolarized if a stimulus decreases its voltage from the resting potential of –70 mV in the
direction of zero voltage.
Deposit-feeder
A heterotroph, such as an earthworm, that eats its way through detritus, salvaging bits and
pieces of decaying organic matter.
Dermal tissue system
The protective covering of plants; generally a single layer of tightly packed epidermal cells
covering young plant organs formed by primary growth.
Dermis
The inner layer of the skin, beneath the epidermis.
Desmosome
A type of intercellular junction in animal cells that functions as an anchor.
Determinate cleavage
A type of embryonic development in protostomes that rigidly casts the developmental fate
of each embryonic cell very early.
Determinate growth
A type of growth characteristic of animals, in which the organism stops growing after it
reaches a certain size.
ff
(ff)
#1