The Limits of the External Validity of the Effects of Each

question 13

Multiple Choice

The limits of the external validity of the effects of each of the two independent variables in a complex design are specified when

• A)there is no interaction effect of the two variables but significant main effects for both variables.
• B)there is no interaction effect of the two variables and neither variable produces a main effect.
• C)there is no interaction effect of the two variables and one independent variable has a main effect but the other variable does not.
• D)there is an interaction effect of the two variables and main effects of the variables may or may not be present.

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Definitions:

Trophoblast

The outer layer of cells that develops in the germinal period. These cells provide nutrition and support for the embryo.

Germinal Period

The period of prenatal development that takes place in the first two weeks after conception. It includes the creation of the zygote, continued cell division, and the attachment of the zygote to the uterine wall.

Ectoderm

The outermost layer of cells or tissue of an embryo in early development, giving rise to the skin and nervous system.

Prenatal Development

The progression of maturation and evolution inside the uterus from the moment of conception until the time of delivery.