Approximately When Did Primitive Cells First Appear on Earth

question 47

Multiple Choice

Approximately when did primitive cells first appear on Earth?

• A)1 billion years ago
• B)2 billion years ago
• C)2.5 billion years ago
• D)3 billion years ago
• E)3.8 billion years ago

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Definitions:

Maternal Cancer Therapy

Treatment aimed at managing cancer during pregnancy, focusing on the health of both the mother and the unborn child.

Gestational Age

The age of an embryo or fetus calculated from the first day of the last menstrual period of the pregnant mother.

Term

In medical context, it refers to the duration of a pregnancy or the gestational age of the fetus, typically measured in weeks.

Popliteal Angle

The angle formed at the knee when the leg is bent at the knee; used in medical examinations to assess hamstring tightness and flexibility.