What must be true for natural selection to occur

Blood has traveled from the heart to the toes. which describes the next step of the circulation process?

Use the above pedigree for questions 1,2, and 3 1. what kind of genetic disorder is represented in the pedigree? a. recessive b. dominate refer to the pedigree in question 1. 2. is the mutated gene in this disorder located on a sex chromosome (x or y) or an autosome? a. sex chromosome b. autosome refer to the pedigree in question 1. 3. which generation has individuals that you are certain are heterozygous for the mutated gene? a. generation 1 b. generation 2 c. generation 3

Which number represents a basic ph, 4 or 9? numerical answers expected! answer for blank 1: i'll give