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Describe the role of calcium ions and ATP during muscle contraction

Calcium ions diffuse from the sarcoplasmic reticulum and bind to troponin. This binding to troponin causes tropomyosin- which at rest blocks the actin-myosin binding sites- moves to expose these binding site...
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Answered by Johanna H. • Biology tutor
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What is the Hardy-Weiberg principle? How do I use the calculations? What are the limitations?

The Hardy-Weinberg principle is used in population genetics. Population genetics is the study of allele frequencies in populations and how they change over time. There are 2 equation used in the Hardy-Weinbe...
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Answered by Jessica L. • Biology tutor
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Maltase is an enzyme found in the body that breaks down maltose. Explain why maltase can only catalyse this reaction?

All enzymes have active sites which are highly specific to their role within the body- the active site being the part of the enzyme in which the enzyme and the substrate (the thing it is reacting with) inter...
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Answered by Johanna H. • Biology tutor
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Describe how heart action is coordinated with reference to the SAN, AVN, and Purkyne Tissue, and explain the importance of the valves within the heart (8 marks)

The SAN (pacemaker) sends a wave of excitation across both atria . This triggers atrial systole, where both atria contract simultaneously . There is a time delay at the AV Node which allows the atria to empt...
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Answered by Octavia B. • Biology tutor
5334 Views

What is the difference between cellular respiration and breathing (respiration)?

Respiration (breathing) is the way your body gets oxygen into the lungs from the air outside.Cellular respiration describes how your cells make ATP - a molecule used to provide energy for chemical reactions.
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Answered by Harry C. • Biology tutor
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