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Question 20N.1A.HL.TZ0.38

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Date November 2020 Marks available [Maximum mark: 1] Reference code 20N.1A.HL.TZ0.38
Level HL Paper 1A Time zone TZ0
Command term Question number 38 Adapted from N/A
38.
[Maximum mark: 1]
20N.1A.HL.TZ0.38

What is the role of calcium ions in muscle contraction?

A. To enable actin to expose binding sites on myosin

B. To bind to troponin, exposing binding sites on actin

C. To prevent an action potential in the muscle membrane

D. To bind to tropomyosin, blocking binding sites on actin

[1]

Markscheme

B

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