WTHS Biology Keystone Exams Biology Keystone Review Packet 10th / 11th Grade Keystone Test Prep ● ● ● ● ● ● ● ● This packet contains helpful information for you to prepare for the upcoming Biology Keystone Test on May 15th and 16th . As you will see, this packet is broken down into several major themes that the Keystone Test will cover. You will be assigned to do parts of this packet over the next several days for a grade. Please take the time to read through and complete each section with your best possible efforts. The preparation you put into this packet and trying to “re-learn” the material will benefit you as if you do well on the test this time, you will not have to take it again. If the score of the test does not meet expectations of the state, the test will need to be taken again. So this is a big deal. We all understand that you still have your regularly scheduled science class and that this is a lot of stuff coming at you (again) in a short amount of time, but we are confident that we can do this together. Refresh your biology memories, advocate for yourself with a science teacher if you do not understand concepts or ideas, put forth a solid effort in completing the tasks and learning the material…it can be done! Major themes covered in this packet: Themes of Life Organic Chemistry Cells and Cell Transport Energy Cell Reproduction & Genetics Protein Synthesis Evolution/Phylogeny Ecology Each section will have major vocabulary words that you should be familiar with, the major content anchors that you should be able to answer questions about, some questions that will refresh your memory and then some practice test questions. A wikispace has been set up to help you be successful in relearning the material. The address of the wikispace is www.udkeystone.wikispaces.com – use this to your advantage. Your teachers have worked very hard to help you – now it is your turn. Cell Reproduction & Genetics Vocabulary Al l e l e Ce l l c y c l e Chr omos ome s Cl oni ng Co‐ domi na nc e Cr os s i ng ov e r Cy t ok i ne s i s DNA r e pl i c a t i on Domi na nt i nhe r i t a nc e Ga me t e Ge ne Ge ne s pl i c i ng Ge ne t he r a py Ge ne r e c ombi na t i on Ge ne t i c e ng i ne e r i ng Ge ne t i c s I nc ompl e t e domi na nc e I nhe r i t a nc e I nt e r pha s e Me i os i s Mi t os i s Mul t i pl e a l l e l e s Nondi s j unc t i on Pol y g e ni c t r a i t Re c e s s i v e i nhe r i t a nc e S e mi c ons e r v a t i v e r e pl i c a t i on S e x ‐ l i nk e d t r a i t Ge ne t i c a l l y modi f i e d or g a ni s m g e not y pe phe not y pe Concepts to Know Main Concept #1: Describe the events that occur during the cell cycle: interphase, nuclear division (i.e. mitosis), cytokinesis. ● T he Ce l l c y c l e – pe r i od of t i me f r om t he be g i nni ng of one c e l l di v i s i on t o t he be g i nni ng of t he ne x t o Dur i ng t he c e l l c y c l e , a c e l l g r ows , pr e pa r e s f or di v i s i on, a nd di v i de s t o f or m t wo da ug ht e r c e l l s , e a c h of whi c h t he n be g i ns t he c e l l c y c l e a g a i n o Cons i s t s of 4 pha s e s ▪ M pha s e – mi t os i s – t he di v i s i on of t he c e l l nuc l e us a nd c y t ok i ne s i s ▪ G1 – i nt e ns e g r owt h a nd a c t i v i t y ▪ S pha s e – c opy i ng of c hr omos ome s ▪ G2 – i nt e ns e g r owt h a nd a c t i v i t y ● G s t a nds f or g a p ● I nt e r pha s e – t i me be t we e n t wo c e l l di v i s i ons o I nt e r pha s e c a n be br ok e n i nt o 3 pha s e s : G1, S , G2 ▪ G1 c e l l s do mos t of t he i r g r owi ng , i nc r e a s i ng i n s i z e a nd s y nt he s i z i ng ne w pr ot e i ns a nd or g a ne l l e s ▪ S c hr omos ome s a r e dupl i c a t e d a nd t he s y nt he s i s of DNA mol e c ul e s t a k e s pl a c e ● Onc e c e l l e nt e r s S pha s e , i t c ompl e t e s c e l l c y c l e ▪ G2 us ua l l y s hor t e s t of 3 pha s e s ● Or g a ne l l e s a nd pr ot e i ns r e qui r e d f or c e l l di v i s i on a r e pr oduc e d ● Ce l l e nt e r s M pha s e onc e c ompl e t e MITOSIS ● 1. o o ▪ ▪ ▪ ● o o 2. o o 3. o o o o 4. o o o o o ▪ ▪ ▪ ● Bi ol og i s t s di v i de t he e v e nt s of mi t os i s i nt o 4 pha s e s : pr opha s e , me t a pha s e , a na pha s e , a nd t e l opha s e pr opha s e – 1st a nd l ong e s t pha s e of mi t os i s ( 50‐ 60% of t ot a l t i me ) c hr omos ome s be c ome v i s i bl e c e nt r i ol e s s e pa r a t e a nd t a k e up pos i t i ons on oppos i t e s i de s of t he nuc l e us f oc a l poi nt t ha t he l ps or g a ni z e s pi ndl e ( f a n‐ l i k e mi c r ot ubul e s t r uc t ur e t ha t he l ps s e pa r a t e t he c hr omos ome s c hr omos ome s a t t a c h t o s pi ndl e a t t he c e nt r ome r e pl a nt s do not ha v e c e nt r i ol e s or g a ni z e s pi ndl e f r om a r e a s c a l l e d c e nt r os ome s nuc l e ol us di s a ppe a r s nuc l e a r e nv e l ope br e a k s down me t a pha s e – 2nd pha s e of mi t os i s c hr omos ome s l i ne up a l ong c e nt e r of t he c e l l mi c r ot ubul e s c onne c t t he c e nt r ome r e of e a c h c hr omos ome t o t he pol e s of t he s pi ndl e a na pha s e – 3rd pha s e of mi t os i s c e nt r ome r e s t ha t j oi n t he s i s t e r c hr oma t i ds s pl i t c hr oma t i ds s e pa r a t e a nd be c ome i ndi v i dua l c hr omos ome s c hr oma t i ds g e t pul l e d a pa r t , t o t he pol e s of t he s pi ndl e e nds whe n t he y s t op mov i ng t h t e l opha s e – 4 pha s e of mi t os i s c hr omos ome s be c ome l oos e a nd be g i n t o di s pe r s e nuc l e a r e nv e l ope r e f or ms s pi ndl e br e a k s a pa r t a nuc l e ol us r e a ppe a r s c y t ok i ne s i s – di v i s i on of t he c y t opl a s m us ua l l y oc c ur s a t t he s a me t i me a s t e l opha s e i n a ni ma l s , c e l l me mbr a ne pi nc he s i n a t t he mi ddl e i n pl a nt s , c e l l pl a t e f or ms mi dwa y t hr oug h t he c e l l be g i nni ng a t t he c e l l wa l l MEIOSIS ● me i os i s i s a pr oc e s s of r e duc t i on di v i s i on i n whi c h t he numbe r of c hr omos ome s pe r c e l l i s c ut i n ha l f a nd homol og ous c hr omos ome s i n a di pl oi d c e l l a r e s e pa r a t e d o i nv ol v e s t wo di s t i nc t s t a g e s : me i os i s I a nd me i os i s I I o one di pl oi d c e l l be c ome s 4 ha pl oi d c e l l s ● homol og ous – t wo s e t s of c hr omos ome s ( one f r om mom a nd one f r om da d) o i f a c e l l ha s bot h s e t s of c hr omos ome s = di pl oi d ( 2n) ▪ 2 c ompl e t e s e t s of c hr omos ome s wi t h 2 c ompl e t e s e t s of g e ne s o g a me t e s wi t h onl y one s e t of c hr omos ome s = ha pl oi d ( n) ▪ c ont a i n onl y one s e t of g e ne s ● meiosis I – pr i or t o me i os i s I , e a c h c hr omos ome i s r e pl i c a t e d o c hr omos ome s l i ne ‐ up s i mi l a r t o mi t os i s , e x c e pt t he homol og ous c hr omos ome s f or a t e t r a d ( 4 c hr oma t i ds ) ▪ oc c ur s dur i ng pr opha s e I ▪ c r os s i ng ov e r ma y oc c ur – r e s ul t s i n t he e x c ha ng e of a l l e l e s be t we e n homol og ous c hr omos ome s a nd pr oduc e s ne w c ombi na t i ons of a l l e l e s o homol og ous c hr omos ome s s e pa r a t e a nd t wo ne w c e l l s a r e f or me d ● meiosis II – c e l l s f r om me i os i s I e nt e r me i os i s I I o c e l l doe s not unde r g o c hr omos ome r e pl i c a t i on o a na pha s e I I – c hr oma t i ds s e pa r a t e Main Concept #2: Compare the processes of mitotic and meiotic nuclear division. In the table provided, check all of the parts of the cell cycle that apply to the description in the left column. In mitosis, meiosis I, and meiosis II columns – state whether it happens in prophase (P), metaphase (M), anaphase (A), or telophase (T) Description / Event Interphas e Mitosi s Meiosis I Meiosis II Neither Nuc l e a r me mbr a ne br e a k s down S e x c e l l s r e s ul t Da ug ht e r c e l l s a r e i de nt i c a l t o pa r e nt Body c e l l s r e s ul t Chr oma t i ds l i ne up s i ng l e f i l e dur i ng me t a pha s e F i na l c hr omos ome # i s t he s a me a s t he pa r e nt c e l l Di pl oi d c e l l s r e s ul t a t e nd Homol og ous c hr omos ome s j oi n T e t r a ds f or m DNA i s r e pl i c a t e d Chr omos ome s a r e doubl e f i l e Cy t ok i ne s i s be g i ns T r a ns c r i pt i on / t r a ns l a t i on oc c ur S pi ndl e f i be r s f or m Ha pl oi d Ce l l s Re s ul t S i s t e r c hr oma t i ds s e pa r a t e Cr os s i ng ov e r ha ppe ns DNA Re pl i c a t i on oc c ur s ● nondi s j unc t i on – f a i l ur e of homol og ous c hr omos ome s t o s e pa r a t e dur i ng me i os i s o i f nondi s j unc t i on oc c ur s , a bnor ma l numbe r s of c hr omos ome s ma y f i nd t he i r wa y i nt o g a me t e s , a nd a di s or de r c hr omos ome numbe r s ma y r e s ul t Main Concept #3: Describe how the process of DNA replication results in the transmission and/or conservation of genetic information. ● DNA Re pl i c a t i on – c opy i ng of DNA o E ns ur e s t ha t e a c h r e s ul t i ng c e l l wi l l ha v e a c ompl e t e s e t of DNA mol e c ul e o Dur i ng DNA r e pl i c a t i on, t he DNA mol e c ul e s e pa r a t e s i nt o t wo s t r a nds , t he n pr oduc e s t wo ne w c ompl e me nt a r y s t r a nds f ol l owi ng t he r ul e s of ba s e pa i r i ng . E a c h s t r a nd of t he doubl e he l i x of DNA s e r v e s a s a t e mpl a t e a g a i ns t whi c h t he ne w s t r a nd i s ma de c a l l e d s e mi c ons e r v a t i v e r e pl i c a t i on Main Concept #4: Explain the functional relationships between DNA, genes, alleles, and chromosomes and their roles in inheritance. ● 1. o o 2. o o ● o T wo c onc l us i ons f r om Me nde l ’ s e x pe r i me nt s wi t h t he pe a pl a nt bi ol og i c a l i nhe r i t a nc e i s de t e r mi ne d by f a c t or s t ha t a r e pa s s e d f r om one g e ne r a t i on t o t he ne x t = genes e a c h g e ne c ont r ol l e d one t r a i t wi t h t wo c ont r a s t i ng c ha r a c t e r s di f f e r e nt f or ms of a g e ne = alleles pr i nc i pl e of domi na nc e – s t a t e s t ha t s ome a l l e l e s a r e domi na nt a nd ot he r s a r e r e c e s s i v e or g a ni s m wi t h domi na nt a l l e l e f or a pa r t i c ul a r f or m of a t r a i t wi l l a l wa y s ha v e t ha t f or m or g a ni s m wi t h r e c e s s i v e a l l e l e f or a pa r t i c ul a r f or m of a t r a i t wi l l ha v e t ha t f or m onl y S e g r e g a t i on – s e pa r a t i on of a l l e l e s Done dur i ng f or ma t i on of g a me t e s ( r e pr oduc t i v e c e l l s ) Main Concept #5: Describe and/or predict observed patterns of inheritance (ie. dominant, recessive, co‐dominance, incomplete dominance, sex‐linked, polygenic, and multiple alleles). ● Pr oba bi l i t y – l i k e l i hood t ha t a pa r t i c ul a r e v e nt wi l l oc c ur o Pr oba bi l i t y of t wo e v e nt s ha ppe ni ng , y ou mul t i pl y t he i ndi v i dua l pr oba bi l i t i e s ▪ o ● ● ● ● ● ● Pa s t out c ome s do not a f f e c t f ut ur e one s T he pr i nc i pl e s of pr oba bi l i t y c a n be us e d t o pr e di c t t he out c ome s of g e ne t i c c r os s e s Punne t t s qua r e – di a g r a m t ha t he l ps de t e r mi ne g e ne c ombi na t i ons t ha t mi g ht r e s ul t f r om a g e ne t i c c r os s Ca pi t a l l e t t e r s r e pr e s e nt domi na nt a l l e l e s ; l owe r c a s e l e t t e r s r e pr e s e nt l owe r c a s e l e t t e r s Homoz y g ous – ha v e t wo i de nt i c a l a l l e l e s – t r ue ‐ br e e di ng He t e r oz y g ous – ha v e t wo di f f e r e nt a l l e l e s – hy br i d – c a r r i e r Phe not y pe – phy s i c a l f e a t ur e Ge nt oy pe – g e ne t i c ma k e ‐ up ● f or t wo g e ne s , a l l e l e s s e g r e g a t e i nde pe nde nt l y o i nde pe nde nt a s s or t me nt – g e ne s s e g r e g a t e i nde pe nde nt l y a nd do not i nf l ue nc e e a c h ot he r ’ s i nhe r i t a nc e ▪ t he pr i nc i pl e of i nde pe nde nt a s s or t me nt s t a t e s t ha t g e ne s f or di f f e r e nt t r a i t s c a n s e g r e g a t e i nde pe nde nt l y dur i ng t he f or ma t i on of g a me t e s ● s ome a l l e l e s a r e ne i t he r domi na nt nor r e c e s s i v e , a nd ma ny t r a i t s a r e c ont r ol l e d by mul t i pl e a l l e l e s or mul t i pl e g e ne s o i nc ompl e t e domi na nc e – one a l l e l e i s not c ompl e t e l y domi na nt ov e r a not he r ▪ he t e r oz y g ous phe not y pe i s s ome whe r e be t we e n t wo homoz y g ous phe not y pe s o c odomi na nc e – bot h a l l e l e s c ont r i but e t o t he phe not y pe of t he or g a ni s m ▪ he t e r oz y g ous phe not y pe s ha v e s ome of bot h homoz y g ous phe not y pe s o mul t i pl e a l l e l e s – g e ne s t ha t ha v e mor e t ha n 2 pos s i bl e a l l e l e s o pol y g e ni c t r a i t s – t r a i t s t ha t r e s ul t f r om t he i nt e r a c t i on of ma ny g e ne s ▪ t he s e t r a i t s a r e a l s o g r e a t l y i nf l ue nc e d by t he e nv i r onme nt Monohybrid Cross 1. T wo f i s h me e t a t t he c or a l r e e f , f a l l i n l ov e , a nd g e t ma r r i e d t ha t s a me ni g ht . T he y de c i de t o ma k e ba bi e s r i g ht a wa y . T he mom f i s h ha s a bi g f l uf f y t a i l ( T T ) whi l e t he da d ha s a v e r y bor i ng f l a t t a i l ( t t ) . T he da d i s wor r i e d t ha t he wi l l pa s s hi s ug l y t a i l down t o hi s k i ds . Wha t i s t he c ha nc e t ha t t he f i r s t c hi l d wi l l ha v e a f l a t t a i l ? T = f l uf f y t a i l t = f l a t t a i l Ge not y pi c Ra t i o: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Phe not y pi c Ra t i o: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Incomplete Dominance: 1. I n J a pa ne s e f our ‐ o’ c l oc k s , t he g e ne f or r e d f l owe r c ol or ( R) i s i nc ompl e t e l y domi na nt ov e r t he whi t e f l owe r c ol or ( r ) . F or e a c h of t he f ol l owi ng s i t ua t i ons , pr e di c t t he g e not y pi c a nd phe not y pi c r a t i os of a r e d pl a nt c r os s e d wi t h a whi t e pl a nt . Codominance 1. T he pa l omi no hor s e i s a hy br i d ( mi x ) s howi ng a g ol de n c oa t wi t h a l i g ht e r ma ne a nd t a i l . A pa i r of c odomi na nt a l l e l e s , D1 a nd D2 i s k nown t o be i nv ol v e d i n t hi s t r a i t . Hor s e s wi t h t he D1D1 g e not y pe a r e c he s t nut c ol or e d, hor s e s wi t h t he D1D2 g e not y pe a r e pa l omi no, a nd hor s e s wi t h t he D2D2 g e not y pe a r e whi t e i n c ol or . A. T wo pa l omi no hor s e s a r e ma t e d by a r t i f i c i a l i ns e mi na t i on. Wha t t y pe s of of f s pr i ng c oul d be pr oduc e d? Sex‐Linked Traits 1. Whi t e e y e d f r ui t f l i e s a r e t he r e s ul t of a s e x ‐ l i nk e d r e c e s s i v e g e ne . S how t he r e s ul t s f r om a c r os s be t we e n a r e d‐ e y e d ( R) ma l e a nd whi t e ‐ e y e d ( r ) f e ma l e f r ui t f l y . Main Concept #6: Explain how genetic engineering has impacted the fields of medicine, forensics, and agriculture (e.g., selective breeding, gene splicing, cloning, genetically modified organisms, gene therapy). s e l e c t i v e br e e di ng – a l l owi ng onl y t hos e a ni ma l s wi t h de s i r e d c ha r a c t e r i s t i c s t o pr oduc e t he ne x t g e ne r a t i on huma ns us e s e l e c t i v e br e e di ng t o pa s s de s i r e d t r a i t s on t o t he ne x t g e ne r a t i on of or g a ni s ms g e ne t i c e ng i ne e r i ng – ma k i ng c ha ng e s i n t he DNA c ode of l i v i ng or g a ni s ms Cut t i ng / S pl i c i ng DNA Re s t r i c t i on e nz y me s – c ut s DNA a t a s pe c i f i c s e que nc e of nuc l e ot i de s c ut t i ng a nd pa s t i ng r e c ombi na nt DNA – t a k i ng DNA a nd “ pa s t i ng ” i t t o a not he r or g a ni s m’ s DNA t r a ns g e ni c or g a ni s ms / g e ne t i c a l l y modi f i e d or g a ni s ms – or g a ni s ms t ha t c ont a i n g e ne s f r om ot he r or g a ni s ms us i ng t he ba s i c t e c hni que s of g e ne t i c e ng i ne e r i ng , a g e ne f r om one or g a ni s m c a n be i ns e r t e d i nt o c e l l s f r om a not he r or g a ni s m. T he s e t r a ns f or me d c e l l s c a n t he n be us e d t o g r ow ne w or g a ni s ms ● c l one – me mbe r of a popul a t i on or g e ne t i c a l l y i de nt i c a l c e l l s pr oduc e d f r om a s i ng l e c e l l ● g e ne t he r a py i s t he pr oc e s s of a t t e mpt i ng t o c ur e g e ne t i c di s or de r s by pl a c i ng c opi e s of he a l t hy g e ne s i nt o c e l l s t ha t l a c k t he m Practice Questions: ● o ● ● o o ▪ ● o 1. Whi c h s t a t e me nt best de s c r i be s t he pha s e of t he c e l l c y c l e s hown? A. T he c e l l i s i n pr opha s e of mi t os i s be c a us e t he numbe r of c hr omos ome s ha s doubl e d. B. T he c e l l i s i n pr opha s e I of me i os i s be c a us e t he numbe r of c hr omos ome s ha s doubl e d. C. T he c e l l i s i n t e l opha s e of mi t os i s be c a us e t he c e l l i s s e pa r a t i ng a nd c ont a i ns t wo c opi e s of e a c h c hr omos ome . D. T he c e l l i s i n t e l opha s e of me i os i s be c a us e t he c e l l i s s e pa r a t i ng a nd c ont a i ns t wo c opi e s of e a c h c hr omos ome . 2. Mi t os i s a nd me i os i s a r e pr oc e s s e s by whi c h a ni ma l a nd pl a nt c e l l s di v i de . Whi c h s t a t e me nt best de s c r i be s a di f f e r e nc e be t we e n mi t os i s a nd me i os i s ? A. Me i os i s i s a mul t i ‐ s t e p pr oc e s s . B. Mi t os i s oc c ur s onl y i n e uk a r y ot i c c e l l s . C. Me i os i s i s us e d i n t he r e pa i r of a n or g a ni s m. D. Mi t os i s pr oduc e s g e ne t i c a l l y i de nt i c a l da ug ht e r c e l l s . Suppose that the central C‐G base pair in the DNA molecule below is substituted by an A‐T base pair. 3. a. b. c. d. 4. a. b. c. d. 5. Wha t i s t he mos t l i k e l y r e s ul t of t hi s mut a t i on? g e ne t i c v a r i a t i on g e ne t i c c l one s i nc ompl e t e t r a ns l a t i on i de nt i c a l of f s pr i ng He mophi l i a i s a n i nhe r i t a bl e g e ne t i c di s or de r t ha t pr ohi bi t s t he pr ope r f or ma t i on of bl ood c l ot s . T he r e c e s s i v e g e ne t ha t c a us e s he mophi l i a i s l oc a t e d on t he X‐ c hr omos ome . Gi v e n t hi s i nf or ma t i on, whi c h of t he f ol l owi ng s t a t e me nt s i s t r ue ? I n or de r f or a ma l e of f s pr i ng t o be a he mophi l i a c , hi s mot he r mus t be a he mophi l i a c . I n or de r f or a f e ma l e of f s pr i ng t o be a he mophi l i a c , he r f a t he r mus t be a he mophi l i a c . I n or de r f or a ma l e of f s pr i ng t o be a he mophi l i a c , hi s f a t he r mus t be a he mophi l i a c . I n or de r f or a f e ma l e of f s pr i ng t o be a he mophi l i a c , he r mot he r mus t be a he mophi l i a c . Whi c h of t he f ol l owi ng s t a t e me nt s i s t r ue ? a. Mi t os i s r e s ul t s i n t he f or ma t i on of t wo ha pl oi d g a me t e s whi c h c a n t he n c ombi ne t o f or m a di pl oi d da ug ht e r c e l l . b. Dur i ng t he pr oc e s s of me i os i s , ha pl oi d c e l l s a r e f or me d. Af t e r f e r t i l i z a t i on, t he di pl oi d numbe r of c hr omos ome s i s r e s t or e d. c. T he pr oc e s s of me i os i s f or ms da ug ht e r c e l l s whi c h a r e g e ne t i c a l l y i de nt i c a l t o t he i r pa r e nt c e l l s . d. T he da ug ht e r c e l l s f or me d dur i ng mi t os i s a r e g e ne t i c a l l y s i mi l a r t o, t houg h not i de nt i c a l t o, t he i r pa r e nt c e l l . 6. Whi c h of t he f ol l owi ng be s t de s c r i be s t he wa y t ha t g e ne s , c hr omos ome s , a nd DNA a r e r e l a t e d? a. Chr omos ome s c ont a i n s e v e r a l g e ne s , whi c h a r e ma de up of s e que nc e s of DNA. b. Ge ne s c ont a i n s e v e r a l c hr omos ome s , whi c h a r e ma de up of s e que nc e s of DNA. c. Ge ne s c ont a i n s e v e r a l s e que nc e s of DNA, whi c h a r e ma de up of c hr omos ome s . d. S e que nc e s of DNA c ont a i n s e v e r a l g e ne s , whi c h a r e ma de up of c hr omos ome s . 7. I f a c a t ha s 38 c hr omos ome s i n e a c h of i t s body c e l l s , how ma ny c hr omos ome s wi l l be i n e a c h da ug ht e r c e l l a f t e r mi t os i s ? a. 19 c . 11 b. 76 d. 38 8. T om i s g oi ng t o buy t wo ha ms t e r s . He wa nt s t o br e e d t he m a nd s e l l t he ba by ha ms t e r s t o a l oc a l pe t s t or e . T he s t or e owne r t e l l s hi m t ha t hi s c us t ome r s pr e f e r da r k br own ha ms t e r s wi t h whi t e be l l i e s , l ong f ur , bl a c k e y e s , a nd l ong t a i l s . T om f ound a f e ma l e ha ms t e r wi t h a l l of t hos e c ha r a c t e r i s t i c s . Whi c h ma l e ha ms t e r s houl d T om buy i n or de r t o ha v e t he BE S T c ha nc e of br e e di ng ba by ha ms t e r s wi t h MOS T of t hos e c ha r a c t e r i s t i c s ? Hamster W _ Hamster X _ Hamster Y _ Hamster Z T a n F ur Da r k Br own F ur T a n F ur Da r k Br own F ur Whi t e Be l l y Whi t e Be l l y Whi t e Be l l y Da r k Br own Be l l y L ong F ur L ong F ur S hor t F ur L ong F ur L ong T a i l L ong T a i l L ong T a i l S hor t T a i l Br own E y e s Br own E y e s Bl a c k E y e s Bl a c k E y e s a. W c . Y b. Z d. X Open‐ended Question: 9. Pa t a u s y ndr ome c a n be a l e t ha l g e ne t i c di s or de r i n ma mma l s , r e s ul t i ng f r om c hr omos ome s f a i l i ng t o s e pa r a t e dur i ng me i os i s . Part A: I de nt i f y t he s t e p dur i ng t he pr oc e s s of me i os i s whe n c hr omos ome s woul d most likely f a i l t o s e pa r a t e . Most likely chromosomes would fair to separate during anaphase I or Anaphase II. In anaphase, chromosomes (anaphase I) or sister chromatids (anaphase II) are supposed to separate, or move AWAY from each other. This is called Nondisjunction. Part B: De s c r i be how c hr omos ome s e pa r a t i on i n me i os i s i s di f f e r e nt f r om c hr omos ome s e pa r a t i on i n mi t os i s . During meiosis cells and the genetic material is divided twice (the first set of division is meiosis I and the second set is meiosis II). In mitosis, the cell and chromosomes divide once. Part C: Compa r e t he e f f e c t s of a di s or de r c a us e d by c hr omos ome s f a i l i ng t o s e pa r a t e dur i ng me i os i s , s uc h a s Pa t a u s y ndr ome , t o t he e f f e c t s of c hr omos ome s f a i l i ng t o s e pa r a t e dur i ng mi t os i s . Due to the improper number of chromosomes, the organism has an improper amount of genetic material in the form of DNA of the sperm or egg. This mutation will be found in every cell of the organism‛s body. If chromosomes fail to separate during mitosis, it does not affect the sex cells but a body cell. This mutant body cell then can be reproduced and produce more of the abnormal cells. The cell either dies or is replicated quickly. This could possibly lead to cancer if the cells are not destroyed by the immune system.
© Copyright 2026 Paperzz