Name the Three Threats to Internal Validity That Can Occur

question 8

Essay

Name the three threats to internal validity that can occur in studies regardless of the use of a comparison group. Why doesn't a comparison group help in these cases?

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Definitions:

Cell Division

A fundamental biological process where a parent cell divides into two or more daughter cells, essential for growth and reproduction.

Blood Cell Formation

The process of creating new blood cells, also known as hematopoiesis, occurring mainly in the bone marrow.

Yolk Sac

One of the extraembryonic membranes that, in shelled vertebrates, contains yolk for the nourishment of the embryo, and in placental mammals is the first site for blood cell formation.

HCG

Human Chorionic Gonadotropin, a hormone produced during pregnancy by the placenta that supports the fetal egg after conception.