---
title: "Sex-Linked Traits — AP Bio Definition & Exam Guide"
description: "Sex-linked traits are genes on the sex chromosomes (usually X) that produce non-Mendelian inheritance patterns, showing up more in males. A core Unit 5 deviation from Mendel."
canonical: "https://fiveable.me/ap-bio/key-terms/sex-linked-traits"
type: "key-term"
subject: "AP Biology"
---

# Sex-Linked Traits — AP Bio Definition & Exam Guide

## Definition

Sex-linked traits are characteristics determined by genes located on the sex chromosomes. They are often seen in males because they have only one X chromosome and therefore express all of the traits it carries, even if they are recessive.

## Related Study Guides

- [5.4 Non-Mendelian Genetics](/ap-bio/unit-5/non-mendelian-genetics/study-guide/5oRHoGlMbML8IgtaHaHs)

## Review

### Related Terms

- X-Linked Inheritance: This refers to the pattern of inheritance for genes located on the X chromosome.
- Y-Linked Inheritance: This refers to the pattern of inheritance for genes located on the Y chromosome.
- Hemizygous: The condition where there is only one allele present instead of two; this typically occurs in males for genes on the X-chromosome.