Answer:
Gastrula
Explanation:
A hollow shaped embryonic structure formed after two weeks of fertilization with three layers is known as gastrula.
The gastrula is formed from the repeated division of the single-layered structured called blastula which later forms three layers called ectoderm, endoderm and mesoderm.
These layers during the process of gastrulation from different organs of the multicellular organisms like the endoderm forms the liver, the ectoderm form the nervous system, the skeletal bone and many others.
Since gastrula structure contains three dermal layers therefore gastrula is the correct answer.
The statement "The American Psychological Association is the only organization that can approve psychological research studies." is false.
Hola!
<span>En la teoría de la música, una escala es cualquier conjunto de notas musicales ordenadas por frecuencia o tono fundamental. Una escala ordenada al aumentar el tono es una escala ascendente, y una escala ordenada por un tono decreciente es una escala descendente.
</span><span>¡Espero que esto ayude!
</span>
~Lauv