Genes in eukaryotes are dispersed and not clustered onto a single operon
1.What is the probability that a sperm from the father will contain the PKU allele?
Probability = ½
2.What is the probability that an egg from the mother will contain the PKU allele?
Probability = ½
3.What is the probability that their next child will have PKU?
Probability = ¼ (because each parent has ½ chance ½ X ½ = ¼)
4.What is the probability that their next child will be heterozygous for the PKU gene?
Probability = ½ (because each parent has ½ chance of donating the ‘P’ allele and ½ chance of donating the ‘p’ allele (½ x ½) + (½ x ½) = ½
An example of a false negative is taking an HIV test and having the test come back negative to say the patient is clean, but in reality they have HIV. Another example of a false negative is a woman taking a pregnancy test saying "not pregnant" (i.e. test is negative), but she actually is pregnant. Between those two examples, it is better to have a false negative pregnancy test because it is non life threatening.
A false positive example would be getting bad news you have cancer, when you actually don't have cancer. Another false positive example is a test saying you have a cold virus, when in actuality you don't. The first example mentioned would have the patient likely go through intense chemo treatments which would greatly affect their livelihood. The second example is a more harmless false positive as it would involve at most a flu shot if anything.