gastrula

American  

[gas-troo-luh] / ˈgæs trʊ lə /

noun

Embryology.

plural

gastrulas, gastrulae

1. 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.

---

gastrula British  

/ ˈɡæstrʊlə /

noun

1. 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

---

gastrula Scientific  

/ găs′trə-lə /

plural

gastrulas

1. 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.

2. ◆ The development of an embryo from blastula to gastrula is called gastrulation.

3. Compare blastula

---

Other Word Forms

• gastrular
  adjective
• pregastrular
  adjective

Etymology

Origin of gastrula

From New Latin, dating back to 1875–80; see origin at gastro-, -ule

Compare meaning

How does gastrula compare to similar and commonly confused words? Explore the most common comparisons:

• blastula vs. gastrula

Example Sentences

"But Haeckel's hypothetical gastrula was a particle-filtering life form, like sponges. In contrast, the predatory gastrula of Aiptasia and other cnidarians possess specialised stinging cells used for capturing prey."

From Science Daily • Sep. 29, 2023

As Prof. Holstein underscores, the data obtained paint a new picture of the predatory lifestyle as a primary characteristic of the cnidarian gastrula.

From Science Daily • Sep. 29, 2023

Thus, Briggs and King concluded5 that the nuclei of cells in the late-stage gastrula have an “intrinsic restriction in potentiality for differentiation”.

From Nature • Oct. 13, 2019

This leads to the formation of the next developmental stage, the gastrula, in which the future digestive cavity is formed.

From Textbooks • Jan. 1, 2015

The young amphioxus has, at this stage, which is called the gastrula stage, a curious parallelism with such a lowly form as the Hydra of our ditches.

From Text Book of Biology, Part 1: Vertebrata by Wells, H. G. (Herbert George)