The nursing student is preparing a presentation which will illustrate the various stages of fetal development. The student will label which stage as the time when the various tissues of the growing embryo begin to assume specific functions?

a. pre-embryonic
b. embryonic
c. fetal
d. post-embryonic

b. embryonic

Explanation:

The embryonic stage is a period that spans from the second week after fertilization to the 8th week after fertilization. The embryonic stage lasts for a short period, but development at the phase brings about a lot of changes.  At this stage of fetal development, cells multiply and various tissues of the growing embryo begin to assume specific functions, also a process, called differentiation.

The pre-embryonic stage starts from fertilization till the end of 2 weeks. At this stage implantation and cellular division occurs.

The fetal stage starts from the beginning of the ninth week after fertilization and continues until birth. At this stage there is additional maturation and growth of the body system.

There is no post-embryonic stage in fetal development.

answer:

convection currents in the magma drive plate tectonics. heat generated from the radioactive decay of elements deep in the interior of the earth creates magma (molten rock) in the aesthenosphere. the aesthenosphere (70 ~ 250 km) is part of the mantle, the middle sphere of the earth that extends to 2900 km.

phaneritic textures in which phaner means visible so phaneritic textures are standard of impertinent volcanic rocks. these rocks crystallized gradually under the surface of earth. when the magma cools deliberately then the ores have chance to develop and produce long crystals.