[gas-troo-luh] /ˈgæs trʊ lə/
noun, plural gastrulas, gastrulae
[gas-troo-lee] /ˈgæs trʊˌli/ (Show IPA). Embryology.
a metazoan embryo in an early state of germ layer formation following the blastula stage, consisting of a cuplike body of two layers of cells, the ectoderm and endoderm, enclosing a central cavity, or archenteron, that opens to the outside by the blastopore: in most animals progressing to the formation of a third cell layer, the mesoderm.
noun (pl) -las, -lae (-ˌliː)
a saclike animal embryo consisting of three layers of cells (ectoderm, mesoderm, and endoderm) surrounding a central cavity (archenteron) with a small opening (blastopore) to the exterior See also ectoderm, mesoderm, endoderm
1877, Modern Latin, from Greek gaster (genitive gastros) “stomach” (see gastric) + Latin -ula, diminutive suffix. Related: Gastrulation.
gastrula gas·tru·la (gās’trə-lə)
n. pl. gas·tru·las or gas·tru·lae (-lē’)
An embryo at the stage following the blastula, consisting of a hollow, two-layered sac of ectoderm and endoderm surrounding an archenteron that communicates with the exterior through the blastopore.
Plural gastrulas or gastrulae (gās’trə-lē’)
An animal embryo at the stage following the blastula. The gastrula develops from the blastula by invagination (inpocketing), forming an inner cavity with an opening and causing the cells to be distributed into an outer layer (ectoderm) and an inner layer (endoderm). In complex animals such as vertebrates, a third layer (mesoderm) also forms. These layers later develop into the organs and tissues of the body. In vertebrates and other deuterostomes, the opening of the gastrula becomes the anus, while in protostomes (such as arthropods), it becomes the mouth. ◇ The development of an embryo from blastula to gastrula is called gastrulation. Compare blastula.
[gas-troo-ley-shuh n] /ˌgæs trʊˈleɪ ʃən/ noun, Embryology. 1. the formation of a gastrula. 2. any process, as invagination, by which a blastula or other form of embryo is converted into a gastrula. /ˌɡæstrʊˈleɪʃən/ noun 1. (embryol) the process in which a gastrula is formed from a blastula by the inward migration of cells gastrulation gas·tru·la·tion […]
noun 1. an electron tube the envelope of which contains a highly rarefied gas.
noun 1. a turbine utilizing the gaseous products of combustion. noun 1. an internal-combustion engine in which the expanding gases emerging from one or more combustion chambers drive a turbine. A rotary compressor driven by the turbine compresses the air used for combustion, power being taken either as torque from the turbine or thrust from […]
- Gas vacuole
noun 1. (biology) a gas-filled structure that provides buoyancy in some aquatic bacteria