Exploring Mendelian Genetics

GENES are more complicated than Mendel thought ____________________________ the ________________________. = ________________________ Genes ________ the ______ for development, but how plan unfolds also _______ on ______________conditions.

Environment influences Phenotype “Nature vs Nurture” Color of hydrangea flowers varies depending on pH of soil Images from:

Environment influences Phenotype “Nature vs Nurture” Siamese cats and Himalayan rabbits have dark colored fur on their extremities Allele that controls pigment production only functions at the lower temperatures Images from slide show by Tracy Nelson

GENES are more complicated than Mendel thought Some traits have ____________ allele __________ = ____________________ EX: blood type Allele choices ___ ___ ___

GENES are more complicated than MENDEL thought Some traits are determined by ____________________________ = __________________ EX: human height. intelligence, skin & eye color

GENES are more complicated than MENDEL thought Traits determined by ____________ _________ have _____ “___________” phenotypes There aren’t just SMART people and DUMB people…. there is a ________________ of intelligences in-between

GENES are more complicated than MENDEL thought KINDS OF DOMINANCE ____________________

COMPLETE DOMINANCE __________ allele _______ the ___________ one PATTERN ? ____________ allele ________ in a _____ratio in the ____ generation

INCOMPLETE DOMINANCE __________ expected _____ ratio in F 2 generation _____________ organisms with one dominant and one recessive allele show a _________ in-between trait Image modified from:

CO-DOMINANCE _______ traits are expressed at ___________ (____________________) in heterozygote A ________HORSE has ______________ hair and __________ hair side by side

CO-DOMINANCE Both traits are expressed together (NO BLENDING) in heterozygote Persons with an A allele AND a B allele have blood type AB

Membrane proteins with _______ attached that help cells recognize self = ______________ REMEMBER

BLOOD TYPES have more than 2 allele choices = _________________________ The pattern of sugars that is attached is determined by genes Allele choices are: _____________

BLOOD TYPES An A allele tells the cell to put “A” glycoproteins on its surface

BLOOD TYPES A B allele tells the cell to put a different “B” glycoprotein on its surface

BLOOD TYPES An O allele tells the cell NOT to put anything on the surface

A and B are CO-DOMINANT A cell with BOTH an A and a B allele has BOTH “A” and “B” glycoproteins on its surface

BLOOD TYPES & ALLELES GENOTYPE PHENOTYPE (BLOOD TYPE) AA AO BB BO OO AB

B and O see A as Different! IMMUNE SYSTEM ATTACKS! Body images modified from: A and AB see A as “like me” DONOR BLOOD

A and O see B as Different! IMMUNE SYSTEM ATTACKS! Body images modified from: B and AB see B as “like me” DONOR BLOOD

Body images modified from: YOU DON’T HAVE ANYTHING I DON’T HAVE! ____ can donate to EVERY BLOOD TYPE = _____________________ Nothing on surface to recognize as “NOT SELF” DONOR BLOOD

A, B, and O see AB as Different! IMMUNE SYSTEM ATTACKS! Body images modified from: Only AB sees AB as “like me” DONOR BLOOD

Body image modified from: ______ can RECEIVE FROM EVERY BLOOD TYPE = ________________________ AB can only GIVE to AB BUT...

BLOOD TYPE FREQUENCY IN USA A40% B10% AB4% O46%

ABO SYSTEM is NOT THE ONLY ONE Rh + Rh -

MOM is _____ & BABY is ____ OTHER BLOOD TYPES ____________________ IF: Image modified from: MOM is _____ & BABY is _____

Can be a ___________ IF: Mom is _____ Baby is _____ Image modified from: 1 st baby OK but few baby cells entering mom’s bloodstream put mom’s immune system on alert for + cells. Next + baby, mom’s immune system can attack baby as it is growing Mom given shot after 1 st birth prevents this

Chromosomes that determine the sex of an organism = _________________ All other chromosomes = _________________ Humans have two sex chromosomes and _____ autosomes

SEX DETERMINATION XX = Xy =

Who decides? Mom can give X Dad can give X or y SO _____ determines sex of the baby. If dad gives X with mom’s X = girl If dad give y with mom’s X = boy X X X y

HEMOPHILIA CAUSE: Mutation in genes for __________________ carried ______ chromosome Blood clotting proteins are missing so person with this disorder can’t stop bleeding when injured; can ________________ from minor cuts or suffer internal bleeding from bruises or bumps.

HEMOPHILIA Treatment: Need ____________ of normal clotting proteins to stop bleeding _____________ in ______ because it is X-linked, but females with ______ recessive hemophilia alleles will also show the trait. 1 in 10,000 males has hemophilia

COLORBLINDNESS CAUSE: Mutation in one of three genes for _______________ carried on X chromosome Persons with this disorder have trouble distinguishing colors. _________________ colorblindness is most common Seen in 1 in 10 males 1 in 100 females

Males ONLY HAVE ONE X They either have the disorder DEFECTIVE NORMAL They don’t Or

FEMALES HAVE TWO X CHROMOSOMES Females have one normal gene that works. NORMALDEFECTIVE Females __________ defective recessive alleles to show the disorder

The X chromosome in males... flies WITHOUT a copilot!... there’s NO BACK UP X to help them!

X-linked cross Dad is not colorblind Mom is colorblind What is the probability of having a colorblind boy? What is the probability of having a colorblind girl? XbXb XbXb XBXB y

Girls with this genotype: X B X b don’t show the COLORBLIND trait They have a “backup” X. BUT.... They can pass the gene onto their offspring.

A heterozygous person who carries a recessive allele for a genetic disorder, but ________ show the trait themselves is called a _____________

DIHYBRID CROSSES ( 2 traits)

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 ______________ traits = ____________________ A Punnett square for a DIHYBRID CROSS looks like this:

Go to Section: Section 11-3 Figure Independent Assortment in Peas

LAW OF __________________________ the factors are distributed to gametes independently of other factors INDEPENDENT ASSORTMENT Image modified from:

1. ___________ what _________________ are 2. ________correct__________ square __________ 3. ______ possible_______________________ 4. ______ boxes with _____________________ 5. Determine ____________of_____________& ____________ LET’S MAKE A DIHYBRID CROSS HOMOZYGOUS YELLOW ROUND HOMOZYGOUS GREEN WRINKLED Figure out parent alleles Choose Punnett size Put in parent gametes Fill in offspring combinations probabilities phenotypes genotypes

__ __ HOMOZYGOUS ROUND YELLOW PRACTICE MAKING GAMETES WHAT ARE THE POSSIBLE GAMETES THIS PARENT CAN MAKE ? Each gamete should get one of each kind of gene ___________ ____________ _____________ _____________

__ __ HOMOZYGOUS WRINKLED GREEN PRACTICE MAKING GAMETES WHAT ARE THE POSSIBLE GAMETES THIS PARENT CAN MAKE ? Each gamete should get one of each kind of gene ___________ ____________ _____________ _____________

__ __ HETEROZYGOUS ROUND YELLOW PRACTICE MAKING GAMETES WHAT ARE THE POSSIBLE GAMETES THIS PARENT CAN MAKE ? Each gamete should get one of each kind of gene ___________ ____________ _____________ _____________

100% of offspring = _______ genotype _______________________ phenotype

HETEROZYGOUS ROUND YELLOW MAKE ANOTHER CROSS

POSSIBLE PARENT GAMETES?

Sign of a ______________________ cross is a _____________ ratio in offspring. ____ Round & Yellow ____ Round & green ____ Wrinkled & yellow ____ wrinkled & green

__________ratio is a clue that it’s a ____________________________cross ____ ____________ TRAIT 1 ; ____________ TRAIT 2 ____ ____________ TRAIT 1; _____________ TRAIT 2

PRACTICE MAKING GAMETES for DIHYBRID CROSSES

pure round & pure tall = __________ ____ ____ ___________ What gametes can it produce? What are the possible gametes?    

Heterozygous Tall = __________ & pure round ____ ____ ___________ What gametes can it produce? What are the possible gametes?    

Hybrid tall = __________ & pure wrinkled ____ ____ ___________ What gametes can it produce? What are the possible gametes?    

Heterozygous tall = __________ & hybrid round ____ ____ ___________ What gametes can it produce? What are the possible gametes?    