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Exploring Mendelian Genetics. http://www.eslkidstuff.com/images/tallshort.gif. http://sps.k12.ar.us/massengale/genetics%20tutorial.htm. Must know terms. Trait—specific characteristic varies from one individual to another example height
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Exploring Mendelian Genetics http://www.eslkidstuff.com/images/tallshort.gif http://sps.k12.ar.us/massengale/genetics%20tutorial.htm
Must know terms Trait—specific characteristic varies from one individual to another example height Hybrid—offspring of crosses between parents with different traits Dominant—expressed trait Recessive—non expressed trait: present only in the absence of the dominant
Must know terms • Homozygous—individuals with two identical alleles for a particular trait –true breeding • Heterozygous—individuals with two different alleles for a particular trait—hybrid • Phenotype—Physical characteristics • Genotype—Genetic makeup
Must know terms • Allele—Different forms of a gene • P generation—Parental generation • F1 generation—first generation after P • F2 generation—second generation after P • Probability—is the likelihood that a particular event will occur
GENES are more complicated than Mendel thought ENVIRONMENT influences ____________________________ the ________________________. = ________________________ Genes ________ the ______ for development, but how plan unfolds also _______ on ______________conditions. expression of genes “Nature vs Nurture” provide plan depends environmental
GENES are more complicated than Mendel thought Some traits have ____________ allele __________ = ____________________ EX: blood type Allele choices ___ ___ ___ choices MORE than 2 MULTIPLE ALLELE TRAIT B O A
GENES are more complicated than MENDEL thought Some traits are determined by ____________________________ = __________________ EX: human height. intelligence, skin & eye color MORE THAN ONE GENE POLYGENIC TRAIT http://www.bcps.org/offices/lis/models/life/images/grow.JPG
GENES are more complicated than MENDEL thought MORE than ONE gene Traits determined by ____________ _________ have _____“___________” phenotypes many in-between There aren’t just SMART people and DUMB people…. there is a ________________ of intelligences in-between whole range http://www.newtonswindow.com/problem-solving.htm
GENES are more complicated than MENDEL thought KINDS OF DOMINANCE ____________________ ____________________ ____________________ COMPLETE DOMINANCE INCOMPLETE DOMINANCE CO-DOMINANCE
COMPLETE DOMINANCE Dominant masks recessive __________ allele _______ the ___________ one PATTERN ?____________ allele ________ in a _____ratio in the ____ generation Recessive returns 3:1 F2 http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookTOC.html
INCOMPLETE DOMINANCE DON’T SEE __________ expected _____ ratio in F2 generation _____________ organisms with one dominant and one recessive allele show a _________ in-between trait 3:1 Heterozygous BLENDED Image modified from: http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookTOC.html
CO-DOMINANCE BOTH SAME TIME NO BLENDING _______ traits are expressed at ___________ (_____________________) in heterozygote ROAN A ________HORSE has ______________ hair and __________ hair side by side BOTH RED WHITE
CO-DOMINANCE Both traits are expressed together (NO BLENDING) in heterozygote Persons with an A alleleAND a B allele have blood type AB
BLOOD TYPES have more than 2 allele choices= _________________________ MULTIPLE ALLELE TRAIT The pattern of sugars that is attached is determined by genes Allele choices are: _____ ____ ____ A B O
BLOOD TYPES & ALLELES A A B B O AB
BLOOD TYPES O ____ can donate to EVERY BLOOD TYPE = _____________________ Nothing on surface to recognize as “NOT SELF” YOU DON’T HAVE ANYTHING I DON’T HAVE! UNIVERSAL DONOR Body images modified from: http://www.new-fitness.com/images/body_shapes.jpg
BLOOD TYPES AB ______ can RECEIVE FROM EVERY BLOOD TYPE = ________________________ UNIVERSAL RECIPIENT Body image modified from: http://www.new-fitness.com/images/body_shapes.jpg
BLOOD TYPE FREQUENCY IN USA http://www.reachoutmichigan.org/funexperiments/agesubject/lessons/newton/BldTyping.html
MENDEL’S PEA EXPERIMENTS true breeding Mendel started his experiments with peas that were _________________ = if allowed to _________________ they would produce ____________________ to themselves. self pollinate offspring identical http://hus.yksd.com/distanceedcourses/YKSDbiology/lessons/FourthQuarter/Chapter11/11-1/images/MendelExperiment.gif
specific characteristic trait A _____________________ is called a ____________ Mendel ______________ in peas. studied 7 traits Pearson Education Inc,; Publishing as Pearson Prentice Hall
MENDEL’S EXPERIMENTS P1 parental ____ generation (_________) ____ generation (______= offspring) ___ generation F1 filial F2
Principles of Dominance Section 11-1 P Generation F1 Generation F2 Generation Tall Short Tall Tall Tall Tall Tall Short
Principles of Dominance Section 11-1 P Generation F1 Generation F2 Generation Tall Short Tall Tall Tall Tall Tall Short
Principles of Dominance Section 11-1 P Generation F1 Generation F2 Generation Tall Short Tall Tall Tall Tall Tall Short
crossed PURE contrasting When Mendel ______________ PLANTS with 2 ______________ traits:(EX: Tall crossed with short) He always found same pattern: 1. ONLY ______ trait ____________ in the ____generation BUT . . . 2. ___________ trait ____________ in the ____ generation in a _________ ratio ONE showed F1 Missing returned F2 3:1
PATTERNS ARE THE KEY Image modified from:http://www.laskerfoundation.org/rprimers/gnn/timeline/1866.html http://www.accessexcellence.org/AB/GG/mendel.html
pair of FACTORS control Mendel decided that there must be a __________________ that ________each trait and that __________ must be able to _______ the other. one factor HIDE
DIHYBRID CROSSES (2 traits) http://mac122.icu.ac.jp/BIOBK/BioBookgenintro.html
Mendel also asked the question? Does the gene that determines if a seed is round or wrinkled have anything to do with the gene for seed shape? Must a seed that is yellow also be round?
MAKING A CROSS with ___________________=____________________ TWO gene traits A Punnett square for a DIHYBRID CROSS looks like this: DIHYBRID CROSS
Figure 11-10 Independent Assortment in Peas Section 11-3
INDEPENDENT ASSORTMENT LAW OF __________________________ the factors are distributed to gametes independently of other factors Image modified from: http://anthro.palomar.edu/mendel/mendel_1.htm
LET’S MAKE A DIHYBRID CROSS HOMOZYGOUS GREEN WRINKLED HOMOZYGOUS YELLOW ROUND rryy RRYY 1. ___________ what _________________ are 2. ________correct__________ square __________ 3. ______ possible_______________________ 4. ______ boxes with _____________________ 5. Determine ____________of_____________& ____________ Figure out parent alleles Choose Punnett size Put in parent gametes Fill in offspring combinations probabilities phenotypes genotypes
PRACTICE MAKING GAMETES WHAT ARE THE POSSIBLE GAMETES THIS PARENT CAN MAKE? HOMOZYGOUS ROUND YELLOW Each gamete shouldget one of each kindof gene RRYY RY RY RY RY ___________ ____________ _____________ _____________
PRACTICE MAKING GAMETES WHAT ARE THE POSSIBLE GAMETES THIS PARENT CAN MAKE? Each gamete shouldget one of each kindof gene HOMOZYGOUS WRINKLED GREEN rryy r y ry ry ry ___________ ____________ _____________ _____________
PRACTICE MAKING GAMETES WHAT ARE THE POSSIBLE GAMETES THIS PARENT CAN MAKE? HETEROZYGOUSROUND YELLOW Each gamete shouldget one of each kindof gene RrYy RY ry rY Ry ___________ ____________ _____________ _____________
ry ry ry ry RY RY RY RY RrYy RrYy RrYy RrYy RrYy RrYy RrYy RrYy RrYy RrYy RrYy RrYy RrYy RrYy RrYy RrYy RrYy 100% of offspring = _______ genotype _______________________ phenotype ROUND YELLOW
MAKE ANOTHER CROSS HETEROZYGOUSROUND YELLOW HETEROZYGOUSROUND YELLOW X RrYy RrYy
POSSIBLE PARENT GAMETES? RY rY ry Ry
RY Ry rY ry RY Ry rY ry ____ Round & Yellow ____ Round & green ____ Wrinkled & yellow ____ wrinkled & green 9 RRYYRRYyRrYY RrYy RRYy RRyy RrYy RryyRrYY RrYyrrYY rrYy RrYyRryy rrYyrryy 3 3 1 heterozygous dihybrid Sign of a ______________________ cross is a _____________ ratio in offspring. 9:3:3:1
9 ____ ____________ TRAIT 1 ; ____________ TRAIT 2 ____ ____________ TRAIT 1; _____________ TRAIT 2 ____ ____________ TRAIT 1; _____________ TRAIT 2 ____ ____________ TRAIT 1; _____________ TRAIT 2 dominant dominant 3 dominant recessive 3 recessive dominant 1 recessive recessive __________ratio is a clue that it’s a ____________________________cross 9:3:3:1 HETEROZYGOUS TWO gene
PRACTICE MAKING GAMETESfor DIHYBRID CROSSES http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookTOC.html
What are the possible gametes? pure round & pure tall = __________ ____ ____ _____ ______ What gametes can it produce? R RTT R T RT RT R T
What are the possible gametes? Heterozygous Tall = __________ & pure round ____ ____ _____ ______ What gametes can it produce? T tRR T R tR tR T R
What are the possible gametes? Hybrid tall = __________ & pure wrinkled ____ ____ _____ ______ What gametes can it produce? T trr T r tr tr T r
What are the possible gametes? Heterozygous tall = __________ & hybrid round ____ ____ _____ ______ What gametes can it produce? T tRr T R tr tR T r