NEET BIOLOGY

Detailed explanation-1: -Gastrulation occurs during week 3 of human development. The process of gastrulation generates the three primary germ layers (ectoderm, endoderm, mesoderm), which primes the system for organogenesis and is one of the most critical steps of development.

Detailed explanation-2: -Gastrulation is a key phase in embryonic development when pluripotent stem cells differentiate into the three primordial germ layers: ectoderm, mesoderm and endoderm.

Detailed explanation-3: -Gastrulation is one of the most critical steps of development, and takes place roughly between days 14 and 21 after fertilization. A single-layered embryo is transformed into a multi-layered structure known as the gastrula.

Detailed explanation-4: -The endoderm is one of the germ layers formed during animal embryogenesis. Cells migrating inward along the archenteron form the inner layer of the gastrula, which develops into the endoderm. It is the first layer to be developed.