When may homo sapiens have first appeared in africa?

Why are scientists concerned about the depletion of the ozone levels in the stratosphere?

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

This connective tissue consists of large round densely packed cells with the nucleus pushed to one side.