DP Biology (last assessment 2024)

Test builder »

Question 18M.3.SL.TZ2.4b.i

Select a Test
Date May 2018 Marks available [Maximum mark: 2] Reference code 18M.3.SL.TZ2.4b.i
Level SL Paper 3 Time zone TZ2
Command term Explain Question number b.i Adapted from N/A
b.i.
[Maximum mark: 2]
18M.3.SL.TZ2.4b.i

The graph shows the energy consumption of photoreceptors in three different species of fly (Drosophila melanogaster, Drosophila virilis and Sarcophaga carnaria) at the mean of the highest transmission rate for each species at rest and while sending a nerve signal (signalling).

(b.i)

Explain how neurons at rest still consume energy.

[2]

Markscheme

a. maintenance metabolism/respiration of the neuron 

b. use of Na-K/sodium potassium pump to maintain resting potential 

c. cell repair «consumes energy»

Syllabus sections