1. an early stage of embryonic development in animals, consisting of a hollow ball of cells
Usage: biology

Examples

• The fertilized egg develops into a blastula within the first few days.
• During the blastula stage, the embryo consists of a single layer of cells surrounding a fluid-filled cavity.
• The blastula will eventually develop into a more complex embryonic structure called a gastrula.
• Scientists study the blastula to understand early embryonic development.
• Cell division continues rapidly during the blastula phase of development.
• The hollow center of the blastula is called the blastocoel.