Ch 5.2 understanding inheritance
- 1. Ch. 5.2 Understanding Inheritance
- 2. Focus Questions 1. What determines the expression of traits? 2. How can inheritance be modeled? 3. How do some patterns of inheritance differ from Mendel’s model?
- 3. 1. What determines the expression of traits? • Mendel concluded that two factors—one from each parent—control each trait (called chromosomes). • Chromosomes are made of coiled up DNA • Genes are segments of DNA for 1 trait.
- 4. 1. What determines the expression of traits? • Remember that DNA stores genetic info. • Alleles – different forms of a gene – Each chromosome has 1 allele for every gene on it. – Ex: Color of pea plant is found in 1 gene, alleles are purple and white • The two chromosomes in an offspring cell may have the same or different alleles.
- 6. 1. What determines the expression of traits? • Phenotype – how a trait physically appears • Genotype – the 2 alleles (genes) that control the phenotype of a trait
- 7. A pea plant that is Yy a. Genotype b. Phenotype 45 Genotype 0 0 Phenotype
- 8. A pea plant that is green a. Genotype b. Phenotype Genotype 0 0 Phenotype 45
- 9. The two alleles a. Genotype b. Phenotype Genotype 0 0 Phenotype 45
- 10. 1. What determines the expression of traits? • Homozygous = same alleles (ex: RR, rr) • Heterozygous = different alleles (ex: Rr)
- 11. What is the genotype? Rr a. Homozygous dominant b. Homozygous recessive c. Heterozygous 45 0 0 0 Homozygous recessive Homozygous dominant Heterozygous
- 12. What is the genotype? ww a. Homozygous dominant b. Homozygous recessive c. Heterozygous 45 0 0 0 Homozygous recessive Homozygous dominant Heterozygous
- 13. What is the genotype? CC a. Homozygous dominant b. Homozygous recessive c. Heterozygous 45 0 0 0 Homozygous recessive Homozygous dominant Heterozygous
- 14. What is the genotype? Yy a. Homozygous dominant b. Homozygous recessive c. Heterozygous 45 0 0 0 Homozygous recessive Homozygous dominant Heterozygous
- 15. 2. How can inheritance be modeled? A Punnett square is a model used to predict possible genotypes and phenotypes of offspring.
- 16. Draw the following Punnett Squares Yy x yy CC x cc
- 17. • Punnett Square Brain Pop
- 18. 2. How can inheritance be modeled? A pedigree shows phenotypes of genetically related family members. Male female Male affected Female affected
- 19. Mrs. Calderon’s family Pedigree for Blue eyes (bb)
- 20. What color are Mrs. Calderon’s dad’s eyes? Mrs. Calderon Mrs. Calderon’s family 0 0 0 Pedigree for Blue eyes (bb) a. Blue b. Dark c. Can’t tell from the chart 60 Blue Dark Can’t tell from the chart
- 21. How many brothers does Mrs. Calderon’s dad have? Mrs. Calderon a. 1 b. 2 c. 3 d. 4 e. 5 f. 6 g. 7 h. 8 i. 9 j. 0 Mrs. Calderon’s family Pedigree for Blue eyes (bb) 0 0 0 0 0 0 0 0 0 0 60 1 2 3 4 5 6 7 8 9 0
- 22. Does Mrs. Calderon carry the blue eye gene? Mrs. Calderon a. Yes b. No c. Can’t tell from the chart Mrs. Calderon’s family 0 0 0 Pedigree for Blue eyes (bb) 60 Yes No Can’t tell from the chart
- 23. Does Mrs. Calderon’s mom carry the blue eye gene? Mrs. Calderon a. Yes b. No c. Can’t tell from the chart 0 0 0 Mrs. Calderon’s family Pedigree for Blue eyes (bb) 60 Yes No Can’t tell from the chart
- 24. 3. How do some patterns of inheritance differ from Mendel’s model? Complex Patterns of Inheritance • Sometimes traits appear to be blends of alleles.
- 25. 3. How do some patterns of inheritance differ from Mendel’s model? Complex patterns of inheritance Incomplete dominance Codominance Polygenic Inheritance Multiple alleles
- 26. 3. How do some patterns of inheritance differ from Mendel’s model? • Incomplete Dominance: when the offspring’s phenotype is a blend of the parents’ phenotypes.
- 28. 3. How do some patterns of inheritance differ from Mendel’s model? • Codominance occurs when both alleles can be observed in a phenotype.
- 30. 3. How do some patterns of inheritance differ from Mendel’s model? Polygenic Inheritance: occurs when multiple genes determine the phenotype of a trait (ex: skin color, eye color).
- 31. 3. How do some patterns of inheritance differ from Mendel’s model?
- 32. • Eye Color
- 33. 3. How do some patterns of inheritance differ from Mendel’s model? Multiple alleles: Some traits are determined by more than one allele; ex: Human ABO blood types
- 34. Genes and the Environment • An organism’s environment can affect its phenotype. • Some examples of environmental factors that affect phenotype are soil type that a flower is growing in or time of year that a butterfly develops.
- 36. What type of inheritance is it when the offspring’s phenotype is a blend of the parents’ phenotypes? A. Incomplete dominance B. Codominance C. Multiple alleles D. Polygenic inheritance 45 Incomplete dominance 0 0 0 0 Multiple alleles Polygenic inheritance Codominance
- 37. What type of inheritance occurs when multiple genes determine the phenotype? A. Incomplete dominance B. Codominance C. Multiple alleles D. Polygenic inheritance 45 Incomplete dominance 0 0 0 0 Multiple alleles Polygenic inheritance Codominance
- 38. What occurs when both alleles can be observed in a phenotype? A. incomplete dominance B. homozygous C. polygenic D. codominance 45 0 0 0 0 B. homozygous A. incomplete dominance C. polygenic D. codominance
- 39. 3. All inherited traits follow Mendel’s patterns of inheritance. a. True b. False 45 True 0 0 False
- 40. 4. Scientists have tools to predict the form of a trait an offspring might inherit. a. True b. False 45 True 0 0 False
Editor's Notes
- #6: 211_links widow gene
- #21: http://www.goldiesroom.org/Shockwave_Pages/REG-18-tnm--punnettsquares.htm
- #30: Hair texture
- #33: cattle coat color (key below) CR = red CW = white CWCR or CRCW = roan (where both red and white are expressed
- #36: Two layers to the eye, back and front. Back is blue (this is why baby’s have blue eyes) the front is controlled by pigment production (Brown/Green) if you have a G then your eyes will create a little pigment in the front layer and you will have green eyes. Example: 3 flasks Add blue to all flasks 2nd flask and a small amount of pigment (yellow) to make green 3rd add more pigment to make brown http://youtu.be/yVLhDUYH_Dc
- #37: in human blood types there 3 possible alleles for the ABO blood typing system IA = A antigen IB = B antigen i = no antigen " both IA and IB are dominant over i but, " both IA and IB are codominant with each other (that means, they are both expressed equally)