The hemoglobin test is often used to check for anemia, usually along with a hematocrit or as part of a complete blood count (CBC) . The test may be used to screen for, diagnose, or monitor a number of conditions and diseases that affect red blood cells (RBCs) and/or the amount of hemoglobin in blood.he hemoglobin test is often used to check for anemia, usually along with a hematocrit or as part of a complete blood count (CBC) . The test may be used to screen for, diagnose, or monitor a number of conditions and diseases that affect red blood cells (RBCs) and/or the amount of hemoglobin in blood.
Volcanoes form at hot spots in the Earth's crust, at convergent plate boundaries where subduction of oceanic crust is occurring, and at divergent plate boundaries where gaps i â¦ n the crust are being infilled with rising magma.
Volcanoes occur where magma rises through the Earth's crust and reaches the surface. To do this, the magma must find a weakness in the crustal rocks on either the land or under the sea.Most of the volcanoes occur at, or close to, the edges of tectonic plates.olcanoes occur where magma rises through the Earth's crust and reaches the surface. To do this, the magma must find a weakness in the crustal rocks on either the land or under the sea.