H1 WA3 (Teacher)

Civics Group Index Number Name (use BLOCK LETTERS) ST ANDREW’S JUNIOR COLLEGE 2022 JC2 Weighted Assessment 3 H1 BIOLOGY 8876 STRUCTURED QUESTIONS & ESSAY 40 minutes READ THESE INSTRUCTIONS FIRST Write your name, civics group and index number on all the work you hand in. Write in dark blue or black pen on both sides of the paper. You may use a soft pencil for any diagram, graph or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. Answer all questions. All working for numerical answers must be shown. Conceptual error (C) Data Quoting (D) Expression (E) Misreading the question (Q) For Examiner’s Use STQ 1 /9 STQ 2 /6 Essay /10 Total /25 This document consists of 5 printed pages. [Turn over H1

QUESTION 1 Due to increase in greenhouse gases, global temperature has been on the rise, including the oceans. Marine organisms like corals are temperature sensitive. Fig. 8.1 shows the distribution of corals over a period of time. Each circle represents a location with corals in it Fig. 1.1 (a) With reference to Fig. 1.1, describe how the distribution of corals has changed from 1975 to 2010 ……………………………………………………………………………………………………………. [4] 1. [Describe trend]: At lower latitudes of 0-20°, coral density decreased from 1990 onwards. 2. [Quote data]: There were 7 locations with higher coral density of 4000-8000 corals/m2 from 1975-1990 while only 1 location had coral density higher than 4000 corals/m2 from 1990-2010 /AVP 3. [Describe trend]: At latitudes >20°, coral density increased from 1990 onwards / Corals have shifted from lower latitudes to higher latitudes. 4. [Quote]: There are hardly any corals found at latitudes >20° from 1975-1990, but saw an increase in coral density from 0 to 4000 corals/m2 from 1990 to 2010. (b) Explain why the change in distribution occurred. ……………………………………………………………………………………………………………. [3] 1. At lower latitudes, warmer ocean temperature placed corals under heat stress 2. Which results in coral bleaching / expelling zooxanthellae 3. Which causes the coral polyps to be more susceptible to other stresses like disease and pollution. 4. At higher latitudes, water previously too cold to support coral and/or zooxanthellae survival are now warm enough to support their growth.

(c) Suggest possible impacts due to the change in distribution of corals. ……………………………………………………………………………………………………………. [2] 1. When the corals shift to higher latitudes, marine species that depend on corals either shift with them, 2. or if unable to shift, become extinct. 3. This can negatively impact the local fishing / ecotourism industry 4. Leads to loss of biomedicine [Total: 9] QUESTION 2 (a) Anopheles gambiae go through four stages in its life cycle. Complete Fig. 2.1 to show these stages. [1] Fig. 2.1 Egg, larvae, pupae and adult; R mosquito for adult (b) Ano