________ plays a role in determining skin color.
A. The HbS allele
B. Ultraviolet radiation
C. Sickle-cell anemia
D. Lactose intolerance
E. Lactose tolerance
Question 2
Some populations like the Polynesians, the San, or the people of southern India have phenotypes that do not fit neatly into standard racial categories, which suggests that
A. it is best to classify humans into a large number of racial categories.
B. phenotypical variation between human populations involves gradual shifts across different geographic zones.
C. these populations must have originated sometime before the major racial groups originated.
D. traditional concepts of race need to be reworked so that they are more exclusive.
E. there has been a lot of gene flow in the time since the origin of the three major human races.
The role of Hox genes 9–13 in specifying limb formation from the proximal to distal
The Sun in false-color ultraviolet image
Role-Play Scenarios
Radiation Quantity and Quality
Phospholipids’ Role in Your Cell Membranes
Layers and Major Structures of the Skin