Looking at the pedigree below, determine the probability that IV-3, and IV-4 are carriers (heterozygous) of PKU. (Their great grandmother, whose circle is shaded, had PKU.)

If second cousins IV-3 and IV-4 were to procreate, what are the odds that they would have a PKU-affected child?

If IV-3 were to marry an unaffected man from the general population, what are the chances that he would be a PKU carrier (is heterozygous)?

What are the chances that they would have a PKU-affected child?

Which of the following characteristics are true of enzymes? check all that apply. a.)the structure of an enzyme can change if conditions change. b.)a single enzyme can normally catalyze a wide variety of reactions under many conditions. c.)enzymes are found only in nonliving systems. d.)enzymes allow living things to regulate body conditions through feedback mechanisms. e.)enzymes bind to specific substrates in specific ways. f.)enzymes increase the rate of reaction. g.)when shown in energy-reaction diagrams, enzymes represent the higher activation energy.