Final answer:
The centrosome contains 2 barrel shaped centrioles surrounded by pericentriolar material and serves as the microtubule-organizing center in animal cells. Each centriole is comprised of nine triplets of microtubules held together by proteins, with the two centrioles lying perpendicular to each other.
Step-by-step explanation:
The structure that contains 2 barrel shaped centrioles surrounded by amorphous, electron-dense pericentriolar material is referred to as the centrosome. The centrosome is a critical component of the cellular machinery, serving as the microtubule-organizing center near the nucleus of animal cells. It plays a pivotal role during cell division, organizing the mitotic spindles that are essential for the separation of chromosomes.
Each centriole within the centrosome is a cylindrical array composed of nine triplets of microtubules, with each triplet arranged in a tubular fashion. These tubules are held together by nontubulin proteins. The two centrioles are typically positioned perpendicular to each other, ensuring the proper coordination and function of the centrosome.