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Ib Exam Paper 2011

Satisfactory Essays

N10/4/BIOLO/HP2/ENG/TZ0/XX

88106002

Biology
HigHER lEvEl
PaPER 2
Candidate session number

Tuesday 2 November 2010 (afternoon)
0

2 hours 15 minutes

0

INSTRUCTIONS TO CANDIDATES
Write your session number in the boxes above.
Do not open this examination paper until instructed to do so.
Section A: answer all of Section A in the spaces provided.
Section B: answer two questions from Section B. Write your answers on answer sheets.
Write your session number on each answer sheet, and attach them to this examination paper and your cover sheet using the tag provided.
• At the end of the examination, indicate the numbers of the questions answered in the candidate box on your cover sheet and indicate the number of sheets used in the appropriate …show more content…

The photograph below of part of a gel shows relative amounts of messenger RNA produced from these three genes by the submergence-intolerant variety, O. sativa japonica, and by the submergence-tolerant variety, O. sativa indica, at different times of a submergence period, followed by a recovery period out of water.
O. sativa japonica

O. sativa indica

Sub1A
Sub1B
Sub1C
0

1

submergence
3

7

10

recovery
R1

R3

0

1

submergence
3

7

Duration of submergence and recovery / days

10

recovery
R1

R3

[Source: Adapted from “Sub1A is an ethylene-response-factor-like gene that confers submergence tolerance to rice” (2006) Kenong Xu, Xia Xu, Takeshi
Fukao, Patrick Canlas, Reycel Maghirang-Rodriguez et al. Nature, 442, pp. 705—708. Adapted by permission from Macmillan Publishers Ltd (c) 2006.]

(c)

(i)

Determine which gene produced the most mRNA on the first day of the submergence period for variety O. sativa japonica.

[1]

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(ii)

Outline the difference in mRNA production for the three genes during the submergence period for variety O. sativa indica.

[2]

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