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Sex-Linked Traits. Chapter 4.1. Answers to Questions. 1. What are sex-linked traits? - Human traits that are carried on the sex chromosomes. 2. What’s a carrier? - A person who has one recessive allele for a trait and one dominant allele.
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Sex-Linked Traits Chapter 4.1
Answers to Questions 1. What are sex-linked traits? - Human traits that are carried on the sex chromosomes. 2. What’s a carrier? - A person who has one recessive allele for a trait and one dominant allele. 3. Males have one X chromosome. Males will be color-blind if they have one allele, and females need two recessive alleles to be colorblind.
Sex-determination • Autosomes --- Non-sex chromosomes; 22 pairs or 44 individual chromosomes. • 23rd pair --- Sex chromosomes; determines gender. XX --- female XY --- male
Sex-influenced Traits • Expressed differently in both sexes due to different hormones which are determined by different sets of genes. • Examples --- male-pattern baldness, horn size in mountain sheep, and feather color in peacocks.
Sex-linked Traits • Traits found on sex chromosomes. • 2 traits that are X-linked inheritance in humans are certain forms of color-blindness & hemophilia. • Hemophilia --- blood disorder where your blood doesn’t clot.