| alae/alar cartilage | the wing-like cartilage which forms the flared portions around the nostrils |
| alveolus | the part of the jawbone that supports the roots of the teeth |
| aminopterin | drug: a folic acid antagonist |
| bilaminar germ disc | the early human embryo, prior to gastrulation, which consists of two germ layers: the epiblast and the hypoblast. These layers will give rise to the embryo itself and extraembryonic structures |
| branchial arches/pharyngeal arches | the paired segmented ridges of tissue in each side of the throat of the early embryo that correspond to the gill arches of the fish. Each arch contains a cartilage, a cranial nerve and a blood vessel |
| columella | 'columella nasi' a part resembling a small column - the anterior part of the nasal septum |
| desmosome | an area of contact between two adjacent cells, especially in epithelium |
| ectoderm | the outer of the three germ layers established at gastrulation. It gives rise to the nervous system, sense organs, teeth, lining of mouth and epidermis and its associated structures |
| endoderm | the inner of the three germ layers of the early embryo. It gives rise to the lining of most of the alimentary tract and associated outgrowths; also the lining of the bronchi and alveoli of lung and the urinary tract |
| filopodia | spikelike projections of cytoplasm containing microfilaments |
| foramen (pl: foramina) | an opening or hole, particularly in a bone |
| histogenesis | the formation of tissues |
| homozygous null | homozygous: the state of having identical alleles at a gene locus in homologous chromosomes. Null: the alleles which determine a particular characteristic have been knocked out, i.e. TGFbeta3 homozygous null mutant mice do not have the gene for TGFbeta3 on either homologous chromosome |
| lingual gingiva | lingual: pertaining to the tongue or structures near it. gingiva: of the gums. Lingual gingiva refers to the inner aspect of the gum of the upper jaw |
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