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.
The volcanoes in this region form a belt called the Ring of Fire. Some of these volcanoes are found in the western United States and Canada. 2. Volcanoes at Divergent Boundaries Volcanoes also form along divergent boundaries where tectonic plates pull apart, allowing magma to rise from the mantle.
1 Pressure builds and magma explodes to the surface causing a volcanic eruption. 2  The lava from the eruption cools to form new crust. 3  After several eruptions, the rock builds up to form a volcano.4  The magma chamber is a collection of magma below the volcano.ey points. 1  Volcanic eruptions can happen at destructive and c onstructive boundaries. 2  Volcanoes form when magma rises through cracks or weaknesses in the Earth's crust. 3  Pressure builds and magma explodes to the surface causing a volcanic eruption. 4  The lava from the eruption cools to form new crust.