How does mafic magma originate from ultramafic rock at a spreading ridge? What will be an ideal response?
As the ultramafic mantle melts to form magma, the first minerals to melt, according to Bowen's
reaction series, are the more felsic minerals in the mantle, quartz, potassium feldspar, and sodium-rich
plagioclase. When the ultramafic rock starts to melt, the felsic minerals have already become part of
the magma, so the magma that erupts at the spreading ridge is more felsic than its source
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High genetic diversity means that almost all of the individuals of a population have the same characteristics.
Answer the following statement true (T) or false (F)
_______________ refers to the volume of pore space in rock in proportion to the total volume of rock material
Fill in the blank(s) with correct word
Which of the following describes a scenario involving pesticide drift?
A) Pesticides run off into a local waterway that flows into a nearby fishing lake, killing some of the sensitive species of fish that live in the lake. B) Pesticides leach into groundwater aquifers, sickening those who use the aquifers for drinking water. C) Pesticides being used in a mountain valley are carried by air currents into the surrounding hills, killing amphibians living in the hills' streams. D) Pesticides contain carcinogens that cause cancer in the workers using the chemicals. E) Pesticides are copied by companies producing generic varieties, but the generic varieties have greater toxic effects than the original pesticides.
An example of coevolution is
a. predators killing their prey. b. one species moving out of an area to find new resources. c. a host species becoming more vulnerable to parasitism. d. a pine tree evolving thicker pinecones to reduce consumption by squirrels after the squirrels evolved stronger jaws to eat the pinecones.