Biology A-Level
sex linkage
What sex linkage means in Biology A-Level, as defined for AQA, OCR.
Definitions of sex linkage
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Reference: OCR
Revealed when reciprocal crosses give different results and when phenotype frequencies differ between the sexes, because males carry one X and express X-linked alleles directly.
Genes lying on sex chromosomes, usually X, where males carry one X-linked allele.
Topics that use sex linkage
- Inheritance (A-level only) (AQA A-Level)
- Patterns of inheritance (OCR A-Level)
Related terms
- critical value
- degrees of freedom
- epistasis
- null hypothesis
- Phenotype
- allele
- Allele frequencies
- Alleles, genotypes and phenotypes
Using sex linkage in the exam
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