In the context of human genetics and biological sex determination, XY refers to the chromosomal makeup that typically indicates a male. According to the reference provided, "an X and a Y chromosome (XY) makes a boy."
Here's a breakdown:
- Chromosomes and Sex: Human cells usually contain 23 pairs of chromosomes, including one pair of sex chromosomes.
- XX vs. XY: These sex chromosomes determine biological sex.
- XX chromosome pairing typically results in a female.
- XY chromosome pairing typically results in a male.
- Scans and Gender Identification: While scans (like ultrasounds) during pregnancy can sometimes provide indications of a baby's sex, the ultimate determination is based on the presence of these chromosomes. Genetic testing can directly identify the presence of XY chromosomes.
Therefore, an XY gender in a scan refers to a male.
