Hello. Attached I have 3 genetic labs that I need assistance with. In some of the questions, it says you'll need to watch the video to answer the questions. This for the most part is not true. I usual

Sara r e alize d th at sh e st ill h ad so me tim e b efo re D r. D ana ca me b ack. S he w ante d to d o it r ig ht th is tim e, m aki ng su re to

a dd a ll typ es of d dN TP s. W hen th e r e act io n r u n co mple te d th is tim e, sh e p ro duce d th e g el p ict ure a s in F ig ure 5 .

F ig ure 5 . G el im age fr o m E xp erim ent 2 .2 .

S ara sh ow ed h er tw o g els to D r. D ana, a little b it e m barra sse d th at sh e h adn’t b een a ble to p ro duce a co rre ct g el w ith

th e tr a ditio nal m eth od. D r. D ana w ave d it a si de b y sa ying, “ N o w orrie s! T his typ e o f m ist ake h appens all th e tim e. T he

m ost im porta nt th in g is to ke ep ta ki ng g ood n ote s in yo ur la b n ote book so w e ca n tr o uble sh oot a nd u nderst and w hat

m ust h ave h appened. I’m h appy to se e yo u d id th at. P le ase g et so me r e st a nd I’ll se e yo u to m orro w m orn in g a s th e

m ach in e is now r e ady.”

T he n ext d ay, S ara b ro ught h er r e act io n tu be to r u n w ith th e se quenci ng m ach in e. T he D NA fr a gm ents in S ara ’s tu be

w ere sca nned b y th e m ach in e a nd r e ad b y a co mpute r. F ig ure 6 is th e ch ro m ato gra m o bta in ed.

Sie rra N etz -D ec 03, 2 021, 1 1 :1 0 A M M ST Fig ure 6 . C hro m ato gra m p ro duce d fr o m S ara ’s exp erim ent.

A nsw er t h e q uestio ns b elo w :

5. K now in g th at S ara h as added a ll th e in gre die nts, w hat co uld b e a r e aso n fo r m issi ng so me o f th e b ands?

(H in t: co nsi der th e q uantity of th e in gre die nts. )

6.

7 . Is th e d ir e ct io n o f th e ch ro m ato gra m fr o m le ft to r ig ht 5 ́ to 3 ́ o r 3 ́ to 5 ́ o f th e se quence ?

8. W hat d oes th e h eig ht o f a p eak in dica te ? ( H in t: co nsi der th e b rig htn ess or th ickn ess of a D NA b and in a n

ele ct ro phore tic gel.)

9 . D o yo u th in k Sara w as able to o bta in th e se quence o f th e p rim er fr o m th e d id eoxy sequenci ng m eth od? E xp la in .

10. T he flu ore sce nt la bel in ve ntio n w as deve lo ped b y Pro fe sso r H ood’s gro up a t C alifo rn ia In st itu te o f T e ch nolo gy. B ut

th ey still h ad to ca rry out se quenci ng in fo ur se para te r e act io n tu bes, u ntil a noth er te am , in th e D uP ont R ese arch L ab,

fu rth er d eve lo ped th e te ch niq ue. W hat sp eci fics about th e la belin g a llo w se quenci ng to b e co nduct ed in a si ngle

r e act io n tu be?

C oncl usi on Dr. D ana w as ve ry ple ase d w ith th e r e su lts and co ngra tu la te d h er n ew in te rn . “ W ell d one S ara ! W e’ve g ot a n ice

ch ro m ato gra m w ith m in im um n oise .”

S ara sm ile d, r e lie ve d th at sh e h ad b een a ble to r e co ver fr o m th e m ist ake sh e h ad m ade ye sterd ay. S he a lso n ow h ad a

b ette r u nderst andin g o f h ow flu ore sce nce a llo w ed a uto m atio n o f se quenci ng, a nd h ow h er w ork was gre atly fa ci lita te d

by th e a bility to ca rry out se quenci ng in a si ngle tu be. T he in itia l w orrie s sh e h ad fe lt a bout h er n ew in te rn sh ip w ere

g one, a nd n ow o nly exci te m ent r e m ain ed.