The process of
prenatal development occurs in three main stages and they are listed in order;
<span>1. </span>Germinal Stage - begins at conception when the
sperm and egg cell joined in one of the two fallopian tubes.
<span>2. </span>Embryonic Stage - begins at the beginning of
the third week after conception. This stage plays an important role in the
development of the brain.
<span>3. </span>Fetal Stage - begins during the ninth week
and lasts until birth.
Lava that hardens on the surface is called an extrusion. The rock layers below an extrusion are always older than the extrusion. ... There, the magma cools and hardens into a mass of igneous rock called an intrusion. An intrusion is always younger than the rock layers around and beneath it.
Water treatment is any process that improves the quality of water to make it more acceptable for a specific end- use. The end use may be drinking, industrial water supply, irrigation,river flow maintenance, water recreation or many other uses, including being safely returned to the enviroment
35 ppt. That is how much salt is in sea water
Less than 4% of the world's water is fresh water and 2/3 of it is underground