GMSS 2018 Bio Prelim P1+2 MS

1 GEYLANG METHODIST SCHOOL (SEC) PRELIMINARY EXAM 2018 SEC 4E P BIOLOGY ANSWERS PAPER 1 1 2 3 4 5 6 7 8 9 10 A C C D B A C B A C 11 12 13 14 15 16 17 18 19 20 C C D B C A C C D C 21 22 23 24 25 26 27 28 29 30 D C D B A D D C D A 31 32 33 34 35 36 37 38 39 40 A B A C A A B D B C PAPER 2Section A 1 (a) (i) - start mass of the onions is different / not all are the same [1]; - use of percentage change in mass allows for valid / fair comparison to determine water potential of the onion [1]; (ii) 183 –175 = 8 ; 8 × 100 = –4.4 [1]; 183 (b) (i) line finished to –4.4 (ii) 44 g dm–3; with indication how value was obtained from graph [1] otherwise 0 m www.KiasuExamPaper.com 21 22 23 24 25 26 27 28 29 30 D C D B A D D C DDDDDDDDDDDDDDDDDDDDD A 31 32 33 34 35 36 37 383838388388383883838383838838383838383 393939339393939393939393939393939399393393 40 A B A C A A B DDDDDDDDDDDDDDDDDDDDDDD BBBBBBBBBBBBBBBBBBBBB CCCCCCCCCCCCCCCCCCCCCC PAPER 2 Section A 1 (a) (i) - start mass of the onions is dididididididddiddididdidddddfffffffffffereeereeeereeeeeeeeerennnnnnnnnnnnnnnnnnnntttttttttttttttttttttttttttttttttt ttttttttt//////////////////////////////////////////////////////////// ////////////////////////////// //////////////////////////nnnonononnononnonoonononononononnnnonononononnnnnononononnnonnoononnonnonononnnnononnnnnononnnnnnnnnnonononnnnnnnonnnnnnoononnnnnnnnnnnnnonnnnnnoonnnnnonnnnnoonnnnonnnonnnnnnononnnnonononnnoooonnnooononnnonooooonnnoooooooonnnoooooooonnooooooooooooooooooooooooooooooooooottttttttttttttttttttttttttttttttt tttttttt ttttttttttttt ttttttttttt t ttttttttttttttttaaaaaaaaallalalaaaaallalalllaalllllalallalalaaallalaaaalalaaaaaaaaaaaaaaaaaaaaaalaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaalalalalallaallalalllaalaallllllllllllllllllllll aareeeeeeeeeeeeeeeeeeee thhhhhhhhhhhhhhhhhhhhhheeeeeeeeeeeeeeeeeeeesamemememememememememememememememmemememmemem[[[[[[[[[[[[[[[[[[[[111111]1111111111111; - use of percentage chchchchchchchchchccchchccchchhhananannnnannnnnnnnnnnnngeggg in mammmmmmmmmmmmmmmmmssssssssssssssssssssssssssssssss allows for vaaaaaaaaaaaaaaaaaaaaalliddddddddddddddddddddddd/ fairrrrrrrrrrrrrrrrrrrrrccccccccccccccccccccccoooooomoooooooooooooooparison to determinewwwwwwwwwwwwwwwwwwatatataatttatataaerpppppppppppppppppppotototototototottottttotttteneneneneneneneneneeeeeeetititittittittttititititttial of thhhhhhhhhhhhhhhhhhe onion [1]; (ii) 183 – 1755555555555555555==============8 ;;;;;;;;;;;; 8 88 888888 8888888888 ×××××××××××××××××××10111110= – 4444.4444444 [1]] ;;;;;;;;;;;;;;;;;; 188888888888888888333333333 (b) (i)))))))))))))))) lililililililililiilillilliiiinefinnnnnnnnnnnnnnnnisssssssssssssssheheheheheheheheheeeheeeheeheddddddddddddddddtototototototototototototott – 4.444444444444444 319

2 (c) -m o v e m e n t o f w a t e r b y o s m o s i s t h r o u g h p a r t i a l l y p e r m e a b l e membrane(s) [1]; - When onion cell sap has lower water potential than sodium chloride solution / sod