BIOLOGY 151 Lecture Notes - Lecture 38: X-Inactivation, Allosome, Zygosity

• School: UMASS-Amherst
• Department: Biology
• Course: BIOLOGY 151
• Professor: kariloomis

Document Summary

Multiple alleles- 3 or more variants in population. Phenotype depends on which 2 alleles are inherited. Codominance- both traits are expressed- type ab. O x ab ii x iaib 50% a, 50% b. A x b iai x ibi 25% a, 25% b, 25% ab, 25% o. X is significantly bigger with significantly more genes. X-linked- genes found on the x but not the y. The x chromosome is larger and is a carrier of more genes. Males are more likely because they just need one recessive allele. Red eyed female fly x white eyed male fly f1 has all red eyes f2 all red eyed females, half red eyed males half white eyed males. Pedigree with almost all males = sex linked color blindness. Sex-influenced inheritance- allele is dominant in one sex, but recessive in the other. Only a woman homozygous for baldness would be bald.