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Question 18N.3.HL.TZ0.14c

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Date November 2018 Marks available [Maximum mark: 2] Reference code 18N.3.HL.TZ0.14c
Level HL Paper 3 Time zone TZ0
Command term Outline Question number c Adapted from N/A
c.
[Maximum mark: 2]
18N.3.HL.TZ0.14c

An investigation into food web interactions was conducted in mesocosms in the Mediterranean Sea, off the coast of France. The effects of the addition of soil and fish on bacterial populations were tested.

(c)

Outline top-down effects on the bacteria in the four mesocosms. 

[2]

Markscheme

a. zooplankton feed on bacteria reducing their numbers ✔

b. fish feed on zooplankton «therefore» increasing bacterial population ✔

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