Abiologist wants to test some lake water for the presence of nitrates. he has a sensor that detects even the tiniest amount of nitrates by turning an internal light from green to red. a) what will be his positive control? (specific). b) what will be his negative control? (specific). c) why does he need o include these controls?

1. the is the thinnest part of the earth. 2. the is the thickest part of the earth. 3. what metals are mentioned in the text?

Someone me with this: a mineral' is determined by its actomic structure.

Which statement is not an accurate description of meiosis? a) meiosis produces offspring that are genetically diverse. b) meiosis produces offspring that are identical to the parent. c) in sexual reproduction half of the genetic material comes from the father (sperm) and half of the genetic material comes from the mother (egg). d) meiosis decreases the number of chromosomes by half so that when a sperm fertilizes an egg, the resulting zygote has the correct number of chromosomes.