biology-dictionary_11-06-2009

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Dichlamydeous
Having two coverings, a calyx and a corolla.
Dicot
A subdivision of flowering plants whose members possess two embryonic seed leaves, or
cotyledons.
Dicotyledon
A member of the class of flowering plants having two seed leaves, or cotyledons, among
other distinguishing features; often abbreviated as dicot.
Dictyosomes
The golgi apparatus in plant cells.
Differentiation
The process by which cells or tissues undergo a change toward a more specialized form or
function, especially during embryonic development.
Diffusion
The spontaneous tendency of a substance to move down its concentration gradient from a
more concentrated to a less concentrated area.
Digestion
The process of breaking down food into molecules small enough for the body to absorb.
Digestive tract
The series of organs in the digestive system through which food passes, nutrients are
absoebed, and waste is eliminated. In higher vertebrates, it consists of the esophagus,
stomach, small and large intestines, rectum, and anus.
Dihybrid
A hybrid individual that is heterozygous for two genes or two characters.
Dihybrid cross
A breeding experiment in which parental varieties differing in two traits are mated.
Dikaryon
A mycelium of certain septate fungi that possesses two separate haploid nuclei per cell.
Dioecious
Referring to a plant species that has staminate and carpellate flowers on separate plants.
Dimorphism
Displaying two separate growth forms.

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