Point source means: the pollution that comes from a single point (examples)
Sewage pipes releasing sewage into a ditch
Smokestack style factory chimneys
Oil pipes
Pollution which is caused by rain fall or snow melting into the ground. As the runoff moves, it picks up and carries away natural and human made pollutants, Finally reaching a lake, river, ocean, groundwater.
That's correct - it's a square where on one axis, the paternal allele (allele = one of the possible forms of the same gene), and on another the maternal allele is listed. Often, it's also indicated whether an allele is recessive or dominant.
Then, in the table that results, all the possible "combinations" of allele between the paternal and maternal party are created. If you count how often a certain combination appears, it indicates the likelihood of that combination.
See the picture (though it is directly from Wikipedia, please note). The likelihood of BB is 25%, of Bb is 50%, and of bb 25%.
The term would be leukocytosis and this usually indicates that there is presence of an infection.