DEATH RATE
the frequency of individuals in a population dying over a set period of time
DECIDUOUS
lost during development; an anatomical reference to primary or “baby” teeth (deciduous dentition)
DELETION
when one or more base pairs is removed from a sequence in DNA as a result of replication errors or mutations
DEMOGRAPHY
a study of the increase or decrease in population size and what may have caused these changes (i.e., survival rates, death rates, reproduction, etc.)
DENS
the odontoid process located on the second cervical vertebrae (the axis)
DENTAL FORMULA
a standardized notation for the total number of incisors, canines, premolars, and molars in the upper and lower jaw seen in an organism. An adult human dental formula is expressed as 2.1.2.3./2.1.2.3
DENTINE
the chief tissue of a tooth; a tissue in the middle of the tooth that surrounds the pulp cavity and is covered by enamel on the crown and cementum on the root of the tooth
DENTITION
teeth
DEOXYRIBONUCLEIC ACID
a nucleic acid based on the five-carbon sugar deoxyribose in a double helix formation; found within chromosomes that carries genetic information. See also DNA.
DERIVED
new; a recently acquired trait.
DESCENT WITH MODIFICATION
genetic material, including mutations, is pass from parent to offspring; the most basic principle of evolution
DIAGNOSTIC
a feature identifiable as a particular aspect
DIAPHYSIS
primary ossification center, or shaft, of long bones
DIASTEMA
a space between teeth
DIPLOIDY
the state of cells containing two copies of each chromosome. Humans are diploids.
DISTAL
a relative term used to describe a part of a limb that is farther from the attachment point to the trunk of the body; the opposite of proximal
DISTAL (DENTITION)
for premolars and molars, a relative term referring to the part of the tooth that is closer to the back of the mouth or throat; the opposite of mesial
DIVERGENCE
[syn. divergent evolution] when genetic or character differences accumulate causing members of the same species to become increasingly different; the opposite of convergent evolution
DNA
the abbreviation for deoxyribonucleic acid
DNA SEQUENCE
the order of nucleotides in DNA
DOMINANT ALLELE
an allele that is expressed in the phenotype regardless of is recessive alternative
DORSAL
a relative term used for quadrupedal organisms (those that travel on four legs) to describe features that are closer to the spine or back of the body; opposite of ventral. The term posterior is a synonym commonly used when referring to bipedal hominin anatomy
DORSIFLEXION
flexing the foot upwards towards the leg