When Teresa's mother hides her favorite doll under a blanket, Teresa acts as if it no longer exists and makes no attempt to look for it. Based on this information, you can infer that Teresa is in Piaget's

Which of the following principles of genetics got its foundation in the work of Gregor Mendel?

a. The idea that a human zygote has 23 pairs of chromosomes. b. The existence of dominant and recessive genes. c. The fact that mitosis and meiosis explain how chromosomes replicate themselves. d. The concept that monozygotic twins share more of their genetic code than dizygotic twins.

__________ has/have contributed to the number of African-American never-married, single-mother families

A) Greater equality for women and more income-earning opportunities B) Traditions dating back to the slave era C) The consequent inability of many black men to support a family D) The widespread availability and generous benefits of child-welfare services