Suppose polymerase chain reaction (pcr) is used to amplify a single dna marker on human chromosome 21. further suppose that a couple who have a child with down syndrome (trisomy 21) is examined for this marker. the mother has marker alleles of 310 and 380 bp. her mate has marker alleles of 290 and 340 bp.

igneous rocks are formed by solidification of cooled magma (molten rock), with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks.  

the composition depends on the source magma. there are almost a thousand types of composition found till now.  

hope this

correct answer: false

while planning water activities, it is very important to consider the weather, because if we do not plan and are going for a surf, then it might be that the hurricane came and drown us or may carry us to long distance from where we can not come back. there are many reasons to take information about the weather when we are planning any water activities.

hence, the correct answer would be false.