Biology is the study of living thing
The four phases of the menstrual cycle are menstruation, the follicular phase, ovulation, and the luteal phase. Common menstrual problems include heavy or painful periods and premenstrual syndrome (PMS). Knowing when in the menstrual cycle a woman is most likely to conceive can increase the chance of pregnancy.
Genetic testing can also be used to determine biological relatives, such as a child's biological parentage (genetic mother and father) through DNA paternity testing, or be used to broadly predict an individual's ancestry.
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