*Question*
Q: What is the name of the two metalloids in the carbon group called? Choices: - titantium and copper - silicon and gold - silver and gold - silicon and germanium A:
**Answer**
silicon and germanium

*Question*
Q: What do you call large, y-shaped proteins that recognize and bind to antigens? Choices: - proteins - membranes - parasites - antibodies A:
**Answer**
antibodies

*Question*
Q: The db gene encodes the which receptor? Choices: - glucose - opioid - estrogen - leptin A:
**Answer**
leptin

*Question*
Q: The outermost layer of the leaf is the epidermis; it is present on both sides of the leaf and is called the upper and lower epidermis, respectively. botanists call the upper side the adaxial surface (or adaxis) and the lower side this? Choices: - dorsal surface - posterior surface - anterior surface - abaxial surface (or abaxis) A:
**Answer**
abaxial surface (or abaxis)