Genetics Textbook: Biology11 Chapter 4
Genetics
Textbook: Biology11 Chapter 4
Heredity
Gregor Mendel Austrian monk (1822-
1884) Worked with pea
plant Readily
distinguishable characteristics
Short generation time Easy to control
pollination
Reproductive
structures offlowers
http://anthro.palomar.edu/mendel/mendel_1.htm
transfer pollen from pollen
parent to seed parent
http://academic.kellogg.cc.mi.us/herbrandsonc/bio111/genetics.htm
http://fig.cox.miami.edu/~cmallery/150/mendel/heredity.htm
Monohybrid Cross (p.3 and 132-137)Tall x Small (homozygous)
http://www.geneticfutures.com/thegift/info/sheet1.asp
The 3 Mendel’s laws (p.2) Mendel's first law (also called the
law of segregation) states that during the formation of gametes (reproductive cells), pairs of allele for a specific trait separate so that offspring receive one factor from each parent.
Mendel’s second law (p.6) Mendel's second law (also called
the law of independent assortment) states that the distribution of alleles for one trait that occurs during the formation of gametes (meiosis) does not affect the distribution of alleles for other traits.
Mendel’s third law Mendel's third law (also called the
law of dominance) states that one of the genes for a pair of inherited traits will be dominant and the other recessive, unless both factors are recessive.
Practice makes perfect Bio 11 p. 137 #1 And genetics worksheet 1
Test Cross: To determine the genotype of a dominant phenotype (p.4)
Practice makes perfect Do genetics worksheet 2 And p. 137-138 # 2 & 4 And p. 140 #5
Dihybrid CrossAnd now, the fun part, the F2 generation
Dihybrid cross (answers for p.5 of booklet)
http://fig.cox.miami.edu/~cmallery/150/mendel/heredity.htm
Practice makes perfect Do genetics worksheet 3 Lab: Genetics of Corn Lab: Virtual Fruit Fly
Multiple alleles (p.6) More than 2 alleles Ex: eye colour of fruit flies
wild type(red) > apricot > honey > white Phenotype genotype
wild type ___apricot ___ honey ___white ___
Multiple alleles (p.6) Exercice E1E4 x E2E3 (red x
apricot)
Incomplete dominance (p.7, 144-145)
Ex: Colour of snapdragons’ flowers Red x White CRCR x CWCW (do Punnett square) Ratio
F2?
Co-dominance (p.9) Another form of incomplete dominance. Ex: red, white, roan cow, ABO blood
groups Alleles: IA, IA, i Group A: antigen ___ : ____ or ____ Group B: antigen ___ : ____ or ____ Group AB: antigen ___ : ____ Group O: antigen ___ : ____
Co-dominance: try this Mother is A Baby is AB Man is O Man is B Who is the father? Show your
answer by drawing the 2 possible Punnett Squares.
Practice makes perfect Do Genetics worksheet 4 Bio 11 p. 145 # 1 & 4.
Lethal genes (p. 9) Read and do Polygenic Inheritance
Polygenic Inheritance (p.9) Characteristic controlled by several
pairs of genes which are independent of each other, often on different chromosomes eg. Eye color, skin color, height
Shows continuous variation
Polygenic inheritance
AB Ab aB ab
AB AABB AABb AaBB AaBb
Ab AABb AAbb AaBb Aabb
aB AaBB AaBb aaBB aaBb
ab AaBb Aabb aaBb aabb
Polygenic inheritance Let’s do bottom of p. 9 together
Polygenic Inheritance with complimentary interaction (p.10)
Pea comb = rrP_ Rose comb = R_pp Walnut comb = R_P_ Single comb = rrpp Let’s do p. 10 together
More practice Genetics worksheet 5
Linkage