BILL PUNNETT PRACTICE Kelly Riedell Brookings Biology Image from: https://biologydictionary.net/wp-content/uploads/2016/11/Punnett-Square.png

Image from: https://blissbiology.files.wordpress.com/2015/04/10-04.gif MENDELIAN GENETICS

Y Yy Yy Yy Yellow y 100% ; 4/4; 4:0 0% ; 0/4; 0:4 HOMOZYGOUS MONOHYBRID (1 gene) CROSSES: PURE-BREEDING YELLOW SEED parent X PURE-BREEDING GREEN SEED parent POSSIBLE OFFSPRING GENOTYPE PHENOTYPE _______ _____________ Y y Yy Yy Yy Yellow What is the probability an offspring will show the DOMINANT TRAIT (YELLOW SEEDS)? ________ What is the probability an offspring will show the RECESSIVE TRAIT (GREEN SEEDS)? ________ 100% ; 4/4; 4:0 0% ; 0/4; 0:4

P Pp Pp Pp p Purple flower 100% ; 4/4; 4:0 0% ; 0/4; 0:4 HOMOZYGOUS PURPLE FLOWER plant X HOMOZYGOUS WHITE FLOWER plant POSSIBLE OFFSPRING GENOTYPE PHENOTYPE _______ _____________ P p Pp Pp Pp Purple flower What is the probability an offspring will show the DOMINANT TRAIT (PURPLE FLOWERS)? ________ What is the probability an offspring will show the RECESSIVE TRAIT (WHITE FLOWERS)? ________ 100% ; 4/4; 4:0 0% ; 0/4; 0:4

T Tt Tt Tt Tall t 100%; 4/4; 4:0 0% ; 0/4; 0:4 HOMOZYGOUS TALL plant X PURE-BREEDING SHORT plant POSSIBLE OFFSPRING GENOTYPE PHENOTYPE _______ _____________ T t Tt Tt Tt Tall What is the probability an offspring will show the DOMINANT TRAIT (TALL)? ________ What is the probability an offspring will show the RECESSIVE TRAIT (SHORT)? ________ 100%; 4/4; 4:0 0% ; 0/4; 0:4

Rr 100 ROUND WRINKLED RECESSIVE SEE A PATTERN FOR HOMOZYGOUS MONOHYBRID CROSSES If you cross plants that are HOMOZYGOUS DOMINANT with plants that are HOMOZYGOUS RECESSIVE for a trait, _______ % of the offspring will show the DOMINANT trait and the ______________ trait will not show at all. ***************************************************************** USE THE PATTERN ABOVE TO MAKE A PREDICTION ABOUT A CROSS WITHOUT A PUNNETT: If you cross a HOMOZYGOUS ROUND SEED plant with a PURE WRINKLED SEED plant 100% of the offspring will look _________ 0% of the offspring will look ____________ The offspring will have 100% probability of having the_______ genotype. 100 RECESSIVE ROUND WRINKLED Rr

BB Bb Bb bb b B B b BB Bb Black bb Brown Black 75%; ¾; 3:1 HETEROZYGOUS MONOHYBRID CROSSES A black coat (B) is DOMINANT in guinea pigs. A brown coat (b) is RECESSIVE. Make a cross between TWO HETEROZYGOUS BLACK guinea pigs. POSSIBLE OFFSPRING GENOTYPE PHENOTYPE _________ _________________ __________ ___________________ B b B b BB Bb Bb bb BB Black Bb Black bb Brown What is the probability that an offspring will be: black? _________ brown? _________ a HYBRID? ________ HOMOZYGOUS DOMINANT ? _________ HOMOZYGOUS RECESSIVE? ___________ 75%; ¾; 3:1 25%; ¼ ; 1:3 50%; ½ ; 2:2 25%; ¼ ; 1:3 25%; ¼ ; 1:3

PP Pp Pp pp P P PP Purple Pp Yellow p Purple p pp 75%; ¾; 3:1 HETEROZYGOUS MONOHYBRID CROSSES Purple fur (P) is DOMINANT in monsters. Yellow fur (p) is RECESSIVE. Make a cross between TWO HETEROZYGOUS PURPLE MONSTERS. . POSSIBLE OFFSPRING GENOTYPE PHENOTYPE _________ _________________ __________ ___________________ P p P p PP Pp Pp pp PP Purple Purple Pp Yellow pp What is the probability that an offspring will be: PURPLE? _________ YELLOW ? _________ a HYBRID? ________ HOMOZYGOUS DOMINANT ? _________ HOMOZYGOUS RECESSIVE? ___________ 75%; ¾; 3:1 25%; ¼ ; 1:3 50%; ½ ; 2:2 25%; ¼ ; 1:3 25%; ¼ ; 1:3

TT Tt Tt tt t T T t TT Tt Tall short tt Tall 75%; ¾; 3:1 25%; ¼ ; 1:3 HETEROZYGOUS MONOHYBRID CROSSES Make a cross between TWO HETEROZYGOUS TALL pea plants POSSIBLE OFFSPRING GENOTYPE PHENOTYPE _________ _________________ __________ ___________________ T t TT Tall T t Tt Tall TT Tt Tt tt short tt What is the probability that an offspring will be: TALL? _________ SHORT? _________ a HYBRID? ________ HOMOZYGOUS DOMINANT ? _________ HOMOZYGOUS RECESSIVE? ___________ 75%; ¾; 3:1 25%; ¼ ; 1:3 50%; ½ ; 2:2 25%; ¼ ; 1:3 25%; ¼ ; 1:3

3 1 75 25 DOMINANT DOMINANT RECESSIVE RECESSIVE SEE A PATTERN FOR HETEROZYGOUS MONOHYBRID CROSSES: If you cross 2 parent plants that are BOTH HETEROZYGOUS for a trait the offspring will show a __ : __ phenotypic ratio (DOMINANT:RECESSIVE) _____ % of the offspring will show the DOMINANT trait and ____ % of the offspring will show the RECESSIVE trait. USE DOMINANT OR RECESSIVE TO FILL IN THE BLANKS BELOW: ¼ of the offspring will have two _____________ alleles, ½ will be hybrids with one ______________ and one ______________ allele, and ¼ will have two _______________ alleles. *****************************************************************u 3 1 75 25 DOMINANT DOMINANT RECESSIVE RECESSIVE

USE THE PATTERN ABOVE TO MAKE A PREDICTION ABOUT A CROSS WITHOUT A PUNNETT: If you cross two HETEROZYGOUS ROUND SEED plants 75% will LOOK ________ 25% will LOOK _________ The probability is: ¼ will have the genotype ______ ½ will have the genotype _____ ¼ will have the genotype _____ ROUND WRINKLED RR Rr rr

DIHYBRID CROSSES

RRYY rryy RY RY RY RY ry RY Parent genotype _____________ ____________ MAKING HOMOZYGOUS TWO GENE CROSSES: HOMOZYGOUS ROUND & YELLOW X PURE-BREEDING WRINKLED & GREEN   Parent genotype _____________ ____________ Possible gametes ____ ____ ____ ____ ____ ____ ____ ____    RRYY rryy RY RY RY RY ry ry ry ry ry RY RrYy RrYy RrYy RrYy RrYy RrYy RrYy RrYy

_______ WRINKLED & YELLOW _______ ROUND & GREEN  WHAT IS THE PROBABILITY AN OFFSPRING WILL BE: _______ ROUND & YELLOW _______ WRINKLED & YELLOW _______ ROUND & GREEN _______ WRINKLED & GREEN *********************************************************  SEE A PATTERN FOR HOMOZYGOUS TWO GENE CROSSES: If you cross plants that are PURE DOMINANT for TWO TRAITS with plants that are PURE RECESSIVE for TWO TRAITS, ________ % of the offspring will look DOMINANT for BOTH traits and the TWO ______________ traits will not show at all.  16/16 0/16 0/16 0/16 100 RECESSIVE

RrYy __________________ RY ry Ry rY

RY Ry rY ry RY Ry rY ry ____ Round & Yellow RRYY RRYy RrYY RrYy ____ Round & green ____ Wrinkled & yellow ____ wrinkled & green RY Ry rY ry RRYY RRYy RrYY RrYy RRYy RRyy RrYy Rryy RrYY RrYy rrYY rrYy RrYy Rryy rrYy rryy

9 RY Ry rY ry . RY Ry rY ry ____ Round & Yellow RRYY RRYy RrYY RrYy ____ Round & green ____ Wrinkled & yellow ____ wrinkled & green 9 RY Ry rY ry RRYY RRYy RrYY RrYy RRYy RRyy RrYy Rryy RrYY RrYy rrYY rrYy RrYy Rryy rrYy rryy .

9 RY 3 Ry rY ry RY Ry rY ry ____ Round & Yellow RRYY RRYy RrYY RrYy ____ Round & green ____ Wrinkled & yellow ____ wrinkled & green 9 RY Ry rY ry RRYY RRYy RrYY RrYy RRYy RRyy RrYy Rryy RrYY RrYy rrYY rrYy RrYy Rryy rrYy rryy 3

9 RY 3 Ry 3 rY ry RY Ry rY ry ____ Round & Yellow RRYY RRYy RrYY RrYy ____ Round & green ____ Wrinkled & yellow ____ wrinkled & green 9 RY Ry rY ry RRYY RRYy RrYY RrYy RRYy RRyy RrYy Rryy RrYY RrYy rrYY rrYy RrYy Rryy rrYy rryy 3 3

9 RY 3 Ry 3 rY ry RY Ry rY ry 1 ____ Round & Yellow ____ Round & green ____ Wrinkled & yellow ____ wrinkled & green 9 RY Ry rY ry RRYY RRYy RrYY RrYy RRYy RRyy RrYy Rryy RrYY RrYy rrYY rrYy RrYy Rryy rrYy rryy 3 3 1

__________ratio is a clue that it’s a 9 ____ ____________ 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

round purple round white wrinkled purple wrinkled white USE THE PATTERN TO MAKE A CROSS WITHOUT A PUNNETT CROSS TWO HETEROZYGOUS ROUND & PURPLE parents The probability is : 9/16 will be _________________ & _________________ 3/16 will be _________________ & _________________ 3/16 will be _________________ & _________________ 1/16 will be _________________ & _________________ round purple round white wrinkled purple wrinkled white

NON-MENDELIAN GENETICS - Sex-linked traits Image from: https://biologydictionary.net/wp-content/uploads/2016/11/Punnett-Square.png NON-MENDELIAN GENETICS - Sex-linked traits

COMPLETE DOMINANCE 3:1 Dominant allele completely masks the recessive one. PATTERN ? F1- All show ___________ phenotype F2- __________ trait returns In a _____ratio Dominant Recessive 3:1 http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookTOC.html

INCOMPLETE DOMINANCE Heterozygous BLENDED EX: SNAPDRAGONS _______________ organisms with one dominant and one recessive allele show a ____________ in-between trait Heterozygous BLENDED Image modified from: http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookTOC.html

RR RW RW WW W R R W RR RW 25% Red flowers 50% Pink flowers 25% WW HETEROZYGOUS INCOMPLETELY DOMINANT SNAPDRAGON PLANTS In snapdragons, red flowers (R) is INCOMPLETELY DOMINANT to white flowers (W) Make a cross between TWO HETEROZYGOUS snapdragon plants. POSSIBLE OFFSPRING PROBABILITY GENOTYPE PHENOTYPE _________ ______ _______________ _________ ________ __________________ __________ __________ ___________________ R W R W RR RW RW WW 25% RR Red flowers 50% RW Pink flowers 25% WW White flowers

CODOMINANCE NO ____________ CODOMINANCE NO ____________. BOTH ALLELES show together at the ____________ at the same time. BLENDING SIDE BY SIDE. In chickens, alleles for BLACK (B) and WHITE (W) color are CODOMINANT. Heterozygous chickens with BW show a speckled (ERMINETTE) phenotype. BB WW BW

BB BW BW WW W B B W BB BW 25% Black 50% 25% WW White HETEROZYGOUS INCOMPLETELY DOMINANT Black chickens (B) is INCOMPLETELY DOMINANT TO white chickens (W) Make a cross between TWO HETEROZYGOUS ERMINETTE chickens. POSSIBLE OFFSPRING PROBABILITY GENOTYPE PHENOTYPE _________ ______ _______________ _________ ________ __________________ __________ __________ ___________________ B W B W BB BW BW WW 25% BB Black Erminette (black & white) 50% BW 25% WW White

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

Membrane proteins with sugars attached that help cells recognize self = ____________________ Responsible for blood type Multiple allele trait =more than 2 choices _____ _____ _____ http://www.mannanw.com/super-sugars.htm GLYCOPROTEINS A B O IA IB i

PHENOTYPE (BLOOD TYPE) BLOOD TYPES & ALLELES GENOTYPE PHENOTYPE (BLOOD TYPE) IA IA OR IA i IB IB OR IB i IA IB i i A B AB O IA i _____ allele is dominant to _____ allele. _____ allele is dominant to _____ allele. _____ and _____ are CODOMINANT BOTH SHOW TOGETHER IB i IA IB

MOM with IA i genotype X DAD with IB i genotype IA IB IA i IB i i i POSSIBLE OFFSPRING PROBABILITY GENOTYPE PHENOTYPE (BLOOD TYPE) _________ ________ _______ _________ _________ _______ __________ _________ _______ __________ _________ ________ 25% AB IA IB A 25% IA i 25% IB i B 25% i i O

MOM with IAi genotype X DAD with IB IB genotype IA IB IA IB IB i IB i POSSIBLE OFFSPRING PROBABILITY GENOTYPE PHENOTYPE (BLOOD TYPE) _________ ________ _______ _________ _________ _______ 50% AB IA IB B 50% IB i

IB i IA IB IA IA IA IB IA i IA IB IA IB IB i IB i IB i i i i i Wanda thinks either Ralph or Fred could be the father of her baby. Wanda’s genotype is IA i. Wanda’s baby has type O blood. Ralph’s genotype is IAIB. Fred’s genotype is IB i.   Ralph X Wanda Fred X Wanda IA IB IB i IA i IA i IA IB IA IB IB i IB i IA IB IA i IB i i i IS IT POSSIBLE RALPH IS THE FATHER? YES NO IS IT POSSIBLE FRED IS THE FATHER? YES NO DOES IT PROVE IT’S FRED? YES NO ANYONE WITH AN i ALLELE COULD BE THE DAD

NON-MENDELIAN GENETICS - Sex-linked traits Image from: https://biologydictionary.net/wp-content/uploads/2016/11/Punnett-Square.png NON-MENDELIAN GENETICS - Sex-linked traits

X y 44 autosomes XX Xy Sex chromosomes Chromosomes that determine http://www.angelbabygifts.com/ Chromosomes that determine the sex of an organism = _________________ All other chromosomes = _________________ Humans have two sex chromosomes ___ and ___ and _____ autosomes Females = _____ Males = _____ Sex chromosomes autosomes X y 44 XX Xy

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

SEX-LINKED GENES Y-linked genes: ▪ Hairy pinna ▪ SRY- master gene that turns on other genes Activation cascade makes developing embryo MALE X-linked genes (X-linked recessive disorders) ▪ Blood clotting factors (Hemophilia) ▪ Eye color receptors (Color blindness) ▪ Muscle proteins (Duchenne Muscular Dystrophy) MALES X-linked traits show up more frequently in ________ No backup X to cover for the “broken” gene Pass mutation to __________ Females can show trait if they inherit _____ mutant X’s Can be _________ for X-linked traits. _______ get mutation from MOM DAUGHTERS TWO CARRIERS SONS

X-LINKED RECESSIVE CROSS Colorblind male X normal vision (non-carrier) female Xc Y Pattern depends on which parent has the mutation! XC XCXc XCY % GENOTYPE PHENOTYPE _____ __________ ___________________ _____ __________ ___________________ 50% XCXc Normal females XCY 50% Normal males

X-LINKED RECESSIVE CROSS Normal male X Color Blind female XC Y Pattern depends on which parent has the mutation! Xc XCXc XcY % GENOTYPE PHENOTYPE _____ __________ ___________________ _____ __________ ___________________ 50% XCXc Normal females XcY 50% Color blind males

XHXh XHY XhXh XhY Xh X-LINKED RECESSIVE % PHENOTYPE Hemophilia male X Normal carrier Female Xh Y XHXh XHY XhXh XhY XH Xh % PHENOTYPE ____ _________________ ____ _____________ ____ _______________ ____ _______________ 25% normal females (carrier) 25% normal males 25% hemophilia females 25% hemophilia males

XDXD XDY XDXd XdY Xd X-LINKED RECESSIVE % PHENOTYPE Normal male X Female (carrier) XD Y Duchenne Muscular Dystrophy XDXD XDY XDXd XdY XD Xd % PHENOTYPE ____ _________________ 25% normal female (carrier) 50% 25% normal female 25% normal male ALL __________ normal ALL DMD’s are _________ females 25% DMD male male

XHXh XhY XHXh XhY X-LINKED DOMINANT % PHENOTYPE ____ _________________ XLH male X normal female XH Y X-linked Hypophosphatemia (XLH) (Vitamin D-resistant rickets) X-LINKED DOMINANT disorder Bone deformities & short stature XHXh XhY XHXh XhY Xh % PHENOTYPE ____ _________________ 50% XLH female 50% normal male males ALL __________ normal ALL XLH’s are _________ female

XHXh XHY XhXh XhY Xh X-LINKED DOMINANT % PHENOTYPE Normal male X XLH female (mom didn’t have XLH) Xh Y X-linked Hypophosphatemia (XLH) (Vitamin D-resistant rickets) X-LINKED DOMINANT disorder Bone deformities & short stature XHXh XHY XhXh XhY XH Xh % PHENOTYPE ____ _________________ 25% XLH female 25% normal female 25% XLH male 25% normal male

TEST CROSSES

Tt TT T T T t Tt Tt Tt tt t HOMOZYGOUS RECESSIVE TEST CROSSES A DOMINANT looking organism could have either of these genotypes: __________ OR __________ Can’t tell which by looking. A test cross is used to determine which it is. ALWAYS TESTCROSS WITH A ____________________________ organism Offspring provide clue about genotype of unknown parent.   TT Tt HOMOZYGOUS RECESSIVE T T T t Tt Tt Tt tt t 100% of offspring will be TALL 50% probability offspring will be TALL 50% probability offspring will be SHORT

T T T t t Tt Tt Tt tt If ANY offspring show the recessive trait . . . unknown parent genotype was _____. If ALL offspring show the dominant trait . . . still don’t know. BOTH genotypes could produce offspring that look dominant! DO ANOTHER TEST CROSS FOR MORE DATA! Tt

Fire breathing (F) is dominant in dragons Fire breathing (F) is dominant in dragons. NON-firebreathing (f) is recessive. You have a fire-breathing dragon. What are its possible genotypes? ______ OR _____ Show the results of test crossing BOTH of the possible parent genotypes. FF Ff F f F F Ff Ff Ff ff f

FF parent can’t make NON-firebreathing offspring. An actual test cross results in a litter with: 6 firebreathing dragons 2 NON-firebreathers What can you conclude about the unknown parent’s genotype? Since test cross produced offspring with recessive phenotype unknown parent genotype must be Ff FF parent can’t make NON-firebreathing offspring.

Dd DD D D D d d Dd Dd Dd Dd Dd dd Deafness in dogs is caused by a recessive allele. Deaf dogs have the genotype dd. You have a hearing dog. What are its possible genotypes? _________ __________ Show the results of test crossing BOTH OF THE POSSIBLE PARENT GENOTYPES: Dd DD D D D d d Dd Dd Dd Dd Dd dd

D d D D Dd dd d Dd Dd Dd Dd An actual test cross results in a litter with: 5 hearing puppies 0 deaf puppies What can you conclude? Both DD and Dd parent could produce these offspring. Parent genotype is still UNKNOWN. Do another test cross to collect more DATA.