Germ layer is a primary layer of cells found in the embryo. The three primary germ layers that generate most of the cells in the developing mammalian forelimb are ectoderm, mesoderm and endoderm.
Ectoderm forms the outer component of a mammalian body such as skin, hair, etc. Endoderm forms the inner layer that comprises of the linings of digestive system, lungs and thyroid. Mesoderm is the middle layer that forms the skeletal system, heart, etc.
Neural tube is generated by the inward folding of the ectoderm. This process is called neurulation. Ectoderm also forms neural crest.
A.) Convention currents in Earth's mantle
Cold ocean water flows from the north pole towards south and affects the climate locations near the Atlantic Ocean.
Hydrogen bonds exhibit the stronger intermolecular force, and water is a polar molecule, so the hydrogen bonding create strong forces which take more energy to break (causing the surface tension of water), and due to the polarity water molecules “stick” to one another which causes the edges to rise up in a tube, forming a meniscus
