Can you help me, please?

E xe rc is e 1 : P ro babilit y P ro bab ilit y = n um ber o f s p ecif ic e ve nts _ _ t o ta l n um ber o f p ossib le e ve nts P ro duct r u le o f p ro bab ilit y : W hen c a lc u la tin g th e p ro babilit y o f c o nse cu tiv e e ve nts , y o u m ult ip ly th e p ro babilit y o f th e in div id ual e ve nts . F or e xa m ple : T he p ro b abilit y o f “ h eads” in a c o in to ss is 0 .5 o r 5 0% . T he p ro babilit y o f g ettin g 2 “ ta ils ” ( o r 2 “ h e ads”) i n a r o w is : ( 0 .5 ) x ( 0 .5 ) = 0 .2 5 o r 2 5% ( 0 .5 fo r th e fir s t c o in t o ss a nd 0 .5 fo r th e s e co nd.) . H ow a bout th e p ro babilit y o f “ h eads”, “ ta ils ”, “ h e ads” i n th at e xa ct o rd er? 0 .5 x 0 .5 x 0 .5 = 0 .1 25 A ddit io n r u le o f p ro bab ilit y : W hen tw o e ve nts , A ( h eads) a nd B ( ta ils ), a re m utu ally e xclu siv e , th e p ro babilit y t h at A o r B w ill o ccu r is th e s u m o f th e p ro babilit y o f e ach e ve nt. In a s in gle c o in flip th e p ro b abilit y o f “ h eads” is 0 .5 a nd th e p ro babilit y o f “ ta ils ” is 0 .5 , th ere fo re t h e p ro babilit y o f h eads o r t a ils is 0 .5 + 0 .5 = 1 ( b ut y o u a lr e ady k n ew th at w hen y o u flip a c o in th ere is a 1 00% c h ance i t w ill la nd e it h er h eads o r ta ils .) B ut r e m em ber: E ven ts t h at h ave a lr e ad y o ccu rre d d o n ot a ffe ct t h e p ro bab ilit y o f f u tu re e ven ts . What is the probability that a couple will have a male child? What is the probability that a couple will have 2 male children? What is the probability that a couple will have 4 male children? A couple has 3 sons and is considering a fourth child, what is the probability that their next child will also be a son?

M akin g th e c o nnectio n b etw een p ro b abilit y a nd P un nett s q uare s: I n th e n ext s e ctio n w e w ill b e u sin g P unnett S qu are s t o e xa m in e in herit a nce o f tr a it s . I n a m atin g b etw een 2 d ip lo id in div id uals , e ach o f th e p are nts c a n p ass o n o ne o f th eir tw o a lle le s fo r a c e rta in tr a it : S o th e p ro babilit y o f a g am ete c a rry in g a lle le “ A ” o f g ene # 1 is a bout 5 0% , a nd th e p ro babilit y o f th at g am ete c a rry in g a lle le “ a ” fo r g ene # 1 is a ls o a ppro xim ate ly 5 0% . H ow d oes th is h elp in s e ttin g u p P unnett s q uare s?

N O TE : T he r a tio s in P unnett S quare s a re r e ally ju st th e p ro b abilit ie s o f e ach p ossib le o utc o m e, n ot h ow m any o f e ach g enoty p e th ere w ill b e.

E xe rc is e 2 . P unnett S quare s t o e stim ate p ro babilit y o f b re edin g o utc o m es. T he w ork sh eet b elo w is d esig ned to h elp y o u u nders ta nd t h e r e la tio nsh ip b etw een g enetic s a nd m eio sis . Y ou w ill a ls o b e in tr o duce d to th e P unnett S quare , a u se fu l t o ol fo r c o m ple tin g g enetic s p ro ble m s. R em em be r th at t h e b est w ay to u nders ta nd g enetic s is to p ra ctic e .

D ra w th e la bele d c h ro m oso m es in e ach c e ll b elo w ( if y o u ju st u se le tte rs , it is d if f ic u lt fo r y o ur in str u cto r t o c h eck y o ur u nders ta ndin g). A s y o u w ork , a nsw er th e q uestio ns i n th e m id dle o f th e d ia gra m . T he tw o c h ro m oso m es w it h in o ne c e ll r e pre se nt a h om olo gous p air . If th e c e lls h ave c o m ple te d S -p hase , th en th e c h ro m oso m es h ave b een d uplic a te d . E ach h alf o f th e “ d uplic a te d” c h ro m oso m e i s a s is te r c h ro m atid .

I m porta nt N ote :

W hen lis tin g g enoty p es, u se th e v o ca bula ry “ h om ozy g ous d om in an t ” , “ h om ozy g ous r e cessiv e ” , a nd “ h ete ro zy g ous ” . ( “ C arrie r ” d escrib es t h e p henoty p e o f u naff e cte d in div id uals w ho h ave o ne c o py o f th e r e ce ssiv e “ d is e ase ” a lle le ; th us th eir g enoty p e is h ete ro zyg ous.) A uto so m al D om in ant D om in ant tr a it s a re th ose th at a re e xp re sse d in th e p henoty p e if th ere is a t le ast o ne c o py o f th e d om in ant a lle le . D om in ant a lle le s c a n p henoty p ic a lly m ask th e p re se nce o f a r e ce ssiv e a lle le . In th e c a se o f d om in ant tr a it s t h e h om ozyg ous d om in ant a nd h ete ro zyg ous g enoty p es w ill h ave th e d om in ant p henoty p e. A uto so m al m eans th at t h e g ene is c a rrie d o n a n on-s e x c h ro m oso m e.

R etin obla sto m a is a n a uto so m al d om in an t d is e ase . R etin obla sto m a c a use s e ye tu m ors . T he g ene fo r th e p ro te in th at w hen a ff e cte d c a use s th e tu m or is fo und o n C hro m oso m e 1 3 ( N IH 2 009). “ R ” r e pre se nts th e r e tin obla sto m a a lle le a nd “ r” r e pre se nts th e n orm al a lle le . A nsw er th e fo llo w in g q uestio ns a bout a c ro ss ( o r m atin g) b etw een a fa th er w ho is “ rr” a nd a m oth e r w ho is “ R R” f o r R etin obla sto m a.

W hat is th e fa th er’s g enoty p e ( h ete ro zyg ous, h om ozyg ous d om in ant, o r h om ozyg ous r e ce ssiv e )?

W hat is th e m oth er’s g enoty p e ( h ete ro zyg ous, h om ozyg ous d om in ant, o r h om ozyg ous r e ce ssiv e )?

W hat is th e fa th er’s p henoty p e ( a ff e cte d, u naff e cte d, c a rrie r)?

W hat is th e m oth er’s p henoty p e ( a ff e cte d, u naff e cte d, c a rrie r)?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e fa th er?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e m oth er?

C om ple te a P unnett s q uare fo r a c ro ss b etw een th ese t w o in div id uals . P are nt # 1 → P are nt # 2 ↓ W hat is th e p re dic te d r a tio o f p hen oty p es f o r th e c ro ss d escrib ed?

A nsw er th e fo llo w in g q uestio ns a bout a c ro ss ( o r m atin g) b etw een a fa th er w ho is “ R r” a nd a m oth e r w ho is “ R r” f o r th e R etin obla sto m a g ene.

W hat is th e fa th er’s g enoty p e ( h ete ro zyg ous, h om ozyg ous d om in ant, o r h om ozyg ous r e ce ssiv e )?

W hat is th e m oth er’s g enoty p e ( h ete ro zyg ous, h om ozyg ous d om in ant, o r h om ozyg ous r e ce ssiv e )?

W hat is th e fa th er’s p henoty p e ( a ff e cte d, u naff e cte d, c a rrie r)?

W hat is th e m oth er’s p henoty p e ( a ff e cte d, u naff e cte d, c a rrie r)?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e fa th er?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e m oth er?

C om ple te a P unnett s q uare fo r a c ro ss b etw een th ese t w o in div id uals . P are nt # 1 → P are nt # 2 ↓ W hat is th e p re dic te d r a tio o f p hen oty p es f o r th e c ro ss d escrib ed? L it e ra tu re c it e d .

N IH 2 009. G enetic s h om e r e fe re nce . < h ttp ://g hr. n lm .n ih .g ov/g ene= r b 1> a cce sse d 2 009 J u ly 1 7.

A uto so m al R ece ssiv e R ece ssiv e tr a it s a re th ose w hic h a re e xp re sse d o nly i f th ere a re n o d om in ant a lle le s p re se nt. In th e c a se o f a uto so m al r e ce ssiv e tr a it s o nly th e h om ozyg ous r e ce ssiv e g enoty p e w ill h ave th e r e ce ssiv e p henoty p e . F or r e ce ssiv e tr a it s , in div id uals w ho a re h ete ro zyg ous a re r e fe rre d to a s c arrie rs . T his is b eca use th ere i s n ot a p henoty p ic e xp re ssio n o f th e tr a it , b ut th e a lle le d oes e xis t a nd c a n b e p asse d o nto o ff s p rin g. C ystic fib ro sis is a n a uto so m al r e ce ssiv e d is e ase . T he c ystic fib ro sis a lle le c a use s a n a bno rm al c h lo rid e i o n c h annel. T his a bnorm ally fu nctio nin g c h a nnel r e su lt s i n h ig h le ve ls o f p ro ductio n o f v is co us m ucu s, w hic h c a n l e ad to in cre ase d r e sp ir a to ry in fe ctio ns. “ C ” r e p re se nts t h e n orm al a lle le . “ c ” r e pre se nts th e c ys tic fib ro sis a lle le .

A nsw er th e fo llo w in g q uestio ns a bout a c ro ss ( o r m atin g) b etw een a fa th er w ho is “ c c” a nd a m oth e r w ho is “ C C”.

W hat is th e fa th er’s g enoty p e ( h ete ro zyg ous, h om ozyg ous d om in ant, o r h om ozyg ous r e ce ssiv e )?

W hat is th e m oth er’s g enoty p e ( h ete ro zyg ous, h om ozyg ous d om in ant, o r h om ozyg ous r e ce ssiv e )?

W hat is th e fa th er’s p henoty p e ( a ff e cte d, u naff e cte d, c a rrie r)?

W hat is th e m oth er’s p henoty p e ( a ff e cte d, u naff e cte d, c a rrie r)?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e fa th er?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e m oth er?

N ow , a nsw er th e fo llo w in g q uestio ns a b out a c ro ss ( o r m atin g) b etw een a fa th er w ho is “ C c” a nd a m oth er w ho is “ C c” fo r C ystic fib ro sis .

W hat is th e fa th er’s g enoty p e ( h ete ro zyg ous, h om ozyg ous d om in ant, o r h om ozyg ous r e ce ssiv e )?

W hat is th e m oth er’s g enoty p e ( h ete ro zyg ous, h om ozyg ous d om in ant, o r h om ozyg ous r e ce ssiv e )?

W hat is th e fa th er’s p henoty p e ( a ff e cte d, u naff e cte d, c a rrie r)?

W hat is th e m oth er’s p henoty p e ( a ff e cte d, u naff e cte d, c a rrie r)?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e fa th er?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e m oth er?

C odom in ance I n s it u atio ns o f c o dom in ance , th ere a re tw o o r m ore d if f e re nt d om in ant a lle le s. B eca use b oth a lle le s a re d om in ant, b oth a re e xp re sse d in th e p henoty p e. T his ty p e o f d om in ance is d is p la ye d in th e “ A BO ” b lo od g ro up . In th is c a se , “ I A ” a nd “ I B ” a re b oth d om in ant, w hile “ io ” is r e ce ssiv e . T he a ll e le “ I A ” r e su lt s in th e e xp re ssio n o f th e ty p e A g ly co pro te in o n b lo od c e lls , t h e a lle le “ I B ” r e su lt s in e xp re ssio n o f th e ty p e B g ly co pro te in o n b lo od c e lls , a nd th e a lle le “ i” r e su lt s in e xp re ssio n o f n eit h er A n or B g ly co pro te in s ( ty p e O ). T here a re m any d if f e re nt h ete ro zyg ous p ossib ilit ie s in th e e xa m ple , e ach o f w hic h w ill h ave a d if f e re nt p henoty p e. T he h ete ro zyg ous I A I B w ill h ave ty p e A g ly co pro te in s a nd ty p e B g ly co pro te in s ( ty p e A B). T he h ete ro zyg ous I A i w ill o nly e xp re ss ty p e A g ly co pro te in s ( ty p e A ). T he h ete ro zyg ous I B i w ill o nly e xp re ss ty p e B g ly co pro te in s ( ty p e B ). A nsw er th e fo llo w in g q uestio ns a bout a c ro ss ( o r m atin g) b etw een a fa th er w ho is “ ii” a nd a m oth er w ho is “ I A I B ” . W hat is th e fa th er’s g enoty p e?

W hat is th e m oth er’s g enoty p e?

W hat is th e fa th er’s p henoty p e ( w hic h b lo od ty p e)?

W hat is th e m oth er’s p henoty p e ( w hic h b lo od ty p e)?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e fa th er?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e m oth er?

N ow , a nsw er th e fo llo w in g q uestio ns a b out a c ro ss ( o r m atin g) b etw een a fa th er w ho is “ I A i ” a nd a m oth er w ho is “ I B i ” . W hat is th e fa th er’s g enoty p e ?

W hat is th e m oth er’s g enoty p e?

W hat is th e fa th er’s p henoty p e ( w hic h b lo od ty p e)?

W hat is th e m oth er’s p henoty p e ( w hic h b lo od ty p e)?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e fa th er?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e m oth er?

C om ple te a P unnett s q uare fo r a c ro ss b etw een th ese t w o in div id uals . P are nt # 1 → P are nt # 2 ↓ W hat is th e p re dic te d r a tio o f p hen oty p es f o r th e c ro ss d escrib ed? I n co m ple te D om in ance I n s it u atio n o f in co m ple te d om in ance , th e h ete ro zyg ous c o ndit io n h as a p henoty p e th at is u niq ue o r in te rm edia te b etw een th e r e ce ssiv e c o ndit io n a nd t h e d om in ant c o ndit io n. T his ty p e o f in he rit a nce i s s e en w it h h um an h air . W hen a n in div id ual h as tw o c o pie s o f th e a lle le " C ", th ey w ill h ave c u rly h air . W he n a n in div id ual h as t w o c o pie s o f th e a lle le " c " th ey w ill h ave s tr a ig ht h air , b ut a h ete ro zyg ous in div id ual " C c" w ill s h ow a n in b etw een o r b le nded p henoty p e a nd h ave w avy h air .

A nsw er th e fo llo w in g q uestio ns a bout a c ro ss ( o r m atin g) b etw een a fa th er w ho is “ c c” a nd a m oth e r w ho is “ C C”. W hat is th e fa th er’s g enoty p e ( h ete ro zyg ous, h om ozyg ous d om in ant, o r h om ozyg ous r e ce ssiv e )?

W hat is th e m oth er’s g enoty p e ( h ete ro zyg ous, h om ozyg ous d om in ant, o r h om ozyg ous r e ce ssiv e )?

W hat is th e fa th er’s p henoty p e ( c u rly , w avy, s tr a ig ht h air )?

W hat is th e m oth er’s p henoty p e ( c u rly , w avy, s tr a ig ht h air )?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e fa th er?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e m oth er?

N ow , a nsw er th e fo llo w in g q uestio ns a b out a c ro ss ( o r m atin g) b etw een a fa th er w ho is “ C c” a nd a m oth er w ho is “ C c” a nd h as w avy h air .

W hat is th e fa th er’s g enoty p e ( h ete ro zyg ous, h om ozyg ous d om in ant, o r h om ozyg ous r e ce ssiv e )?

W hat is th e m oth er’s g enoty p e ( h ete ro zyg ous, h om ozyg ous d om in ant, o r h om ozyg ous r e ce ssiv e )?

W hat is th e fa th er’s p henoty p e ( c u rly , w avy, s tr a ig ht h air )?

W hat is th e m oth er’s p henoty p e ( c u rly , w avy, s tr a ig ht h air )?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e fa th er?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e m oth er?

X -lin ke d D is o rd ers T ra it s c a rrie d o n th e s e x ( X o r Y ) c h ro m oso m es h ave a d if f e re nt in herit a nce p atte rn th an th ose o n t h e a uto so m al c h ro m oso m es. A lt h ough th e X a nd Y c h ro m oso m es l in e u p in m eio sis I, th ey a re n ot h om olo gous a nd d o n ot c a rry th e s a m e g enes. F or th is r e a so n th ere i s o fte n o nly o ne a lle le p re se nt fo r a tr a it r a th er t h an tw o. X -lin ke d d is o rd ers a re c a rrie d o n th e X c h ro m oso m e. F em ale s h ave tw o c o pie s o f th e X c h ro m oso m es, w hile m ale s o nly h ave a s in gle c o py o f th e X c h ro m oso m e. T he c e lls o f m ale s o nly c o nta in a s in gle X c h ro m oso m e, t h ere fo re ; th ey c a nnot b e c o nsid ere d h om ozyg ous o r h ete ro zyg ous fo r th at a lle le . In ste ad th e y a re c o nsid ere d h em iz y g ous , m eanin g th at th ey o nly c a rry a s in gle a lle le fo r th at g ene. F or X -lin ke d r e ce ssiv e d is o rd e rs , b eca use X Y in div id uals a re h em iz yg ous, th ey a re m ore c o m monly a ff e cte d c o m pare d to X X in div id uals . X-linked Dominant F or X -lin ke d d om in ant tr a it s if th e a lle le is p re se nt, i t is e xp re sse d . H yp ophosp hate m ic r ic ke ts is a n X -lin ke d d om in ant d is e ase th at c a use s r ic ke ts ( w eake nin g o f th e b one d ue to a bnorm al o ssif ic a tio n ). “ X R ” r e pre se nts th e H yp ophosp hate m ic r ic ke ts a lle le . “ X r ” r e pre se nts th e n orm al a lle le . A nsw er th e fo llo w in g q uestio ns a bout a c ro ss ( o r m atin g) b etw een a fa th er w ho is “ X r Y ” a nd a m oth er w ho is “ X R X r ” . W hat is th e fa th er’s g enoty p e ( h em iz yg ous d om in ant, o r h em iz yg ous r e ce ssiv e )?

W hat is th e m oth er’s g enoty p e ( h ete ro zyg ous, h om ozyg ous d om in ant, o r h om ozyg ous r e ce ssiv e )?

W hat is th e fa th er’s p henoty p e ( a ff e cte d, u naff e cte d)?

W hat is th e m oth er’s p henoty p e ( a ff e cte d, u naff e cte d, c a rrie r)?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e fa th er?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e m oth er?

X-linked Recessive X -lin ke d r e ce ssiv e tr a it s a re m ore lik e ly to b e e xp re sse d i n m ale s th an in fe m ale s. T his is d ue to t h e h em iz yg ous g enoty p e. If o nly a s in gle a lle le is p re se nt, a nd th at a lle le is r e ce ssiv e , it w ill b e e xp re sse d. In f e m ale s, th ere a re tw o a lle le s, a nd a d om in ant a lle le c a n m ask th e r e ce ssiv e a lle le . H em ophil ia A a ff e cts a ppro xim ate ly 1 in 4 ,0 00 m ale s ( N IH 2 0 09). H em op hilia i s c a use d b y a la ck o f b lo od c lo ttin g fa cto rs . T his c a n r e su lt in e xce ssiv e b le edin g th at d oes n o t s lo w a t a n orm al p ace . “ X H ” r e pre se nts n orm al a lle le . “ X h ” r e pre se nts t h e h em ophilia A a lle le .

A nsw er th e fo llo w in g q uestio ns a bout a c ro ss ( o r m atin g) b etw een a fa th er w ho is “ X h Y ” a nd a m oth er w ho is “ X H X h ” . W hat is th e fa th er’s g enoty p e ( h em iz yg ous d om in ant, o r h em iz yg ous r e ce ssiv e )?

W hat is th e m oth er’s g enoty p e ( h ete ro zyg ous, h om ozyg ous d om in ant, o r h om ozyg ous r e ce ssiv e )?

W hat is th e m oth er’s p henoty p e ( a ff e cte d, u naff e cte d)?

W hat is th e m oth er’s p henoty p e ( a ff e cte d, u naff e cte d, c a rrie r)?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e fa th er?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e m oth er?

D ih yb rid C ro ss D ih yb rid c ro sse s fo llo w th e in herit a nce p atte rn s o f t w o d if f e re nt tr a it s a t th e s a m e tim e. R em em be r th at e ach g am ete m ust g et a n a lle le fo r e ach tr a it , b ut n ot m ore th an o ne b eca use g am ete s a re h a plo id . In fr u it f lie s ( D ro so phila ) , g ra y b ody c o lo r ( G ) is d om in ant to e bon y b ody c o lo r ( g ), w hile lo ng w in gs ( L ) a re d o m in ant t o v e stig ia l w in gs ( l) . V estig ia l w in gs a re s h ort s tu bby w in gs th at h ave n ot d eve lo ped c o m ple te ly . W hen e xa m in in g m ore th an o ne tr a it a t a tim e it is b ette r to lis t t h e a lle le s fo r e ach tr a it to d escrib e th e g e noty p e o f th e in div id ual s in ce th ey c o uld b e h ete ro zyg ous fo r o ne tr a it b ut h om ozyg ous fo r a noth er. S o fo r th e fo llo w in g q uestio ns w rit e t h e g enoty p es w it h b oth a lle le s fo r b oth tr a it s ( e .g . “ G gLl” o r g gLL). A nsw er th e fo llo w in g q uestio ns fo r a c ro ss w here th e m oth er is g ra y b odie d w it h lo ng w in gs a nd th e fa th er i s e bony b odie d w it h v e stig ia l w in gs. A ssu m e b oth p are n ts a re h om ozyg ous fo r b oth tr a it s . W hat is th e fa th er’s g enoty p e a nd p henoty p e?

W hat is th e m oth er’s g enoty p e a nd p henoty p e?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e fa th er?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e m oth er?

W hat is th e g enoty p e a nd p henoty p e o f a ll th e F 1 o ffs p rin g ? S ele ct th e g enoty p e(s ) b elo w th at is /a re p ossib le f o r a g am ete i n th is c ro ss, a ssu m in g M eio sis o ccu rs c o rre ctly . ● G GL ● G L ● G g ● g Ll ● G Gll N ow a nsw er th e fo llo w in g q uestio ns fo r a c ro ss b etw een a m ale a nd a fe m ale fr u it fly th at a re F 1 o ff s p rin g f r o m t h e p re vio us q uestio n:

W hat is th e fa th er’s g enoty p e a nd p henoty p e?

W hat is th e m oth er’s g enoty p e a nd p henoty p e?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e fa th er?

W hat a re th e p ote ntia l g am ete s p ro duce d b y th e m oth er?

C om ple te a P unnett s q uare fo r a c ro ss b etw een th ese t w o in div id uals P are nt # 1 → P are nt # 2 ↓ L it e ra tu re c it e d .

N IH 2 009. G enetic s h om e r e fe re nce . < h ttp ://g hr. n lm .n ih .g ov/g ene= r b 1> a cce sse d 2 009 J u ly 1 7.