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Outline the folding of a protein to form its 3D structure.

Folding of proteins occurs in 4 distinct stages: primary, secondary, tertiary and quaternary. Primary structure is the formation of the amino acid (peptide) sequence, here the amino acids are joined together...
OG
Answered by Olga G. Biology tutor
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Explain the differences between aerobic and anerobic respiration in terms of the roles of co-enzymes

During aerobic respiration, NAD and FAD collect protons and electrons from respiratory substrates. These electrons can be released into the transport chain of the mitochondrial matrix because oxygen is prese...
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Answered by Solomon B. Biology tutor
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Explain the consequences of using high levels of nitrogenous fertilisers

Eutrophication is the process of artificially increasing the mineral content of water as a result of nitrogen-containing fertilisers, especially nitrates, leaching from agricultural land. The nitrates and ph...
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Answered by Jessica W. Biology tutor
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How might you estimate the population size for a species of bird?

As birds are a motile organism, we would use the mark-release-recapture method. First, capture a sample of individuals (possibly through mist netting), mark them (e.g. a wing tag or leg ring) and release. Th...
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Answered by Kieran L. Biology tutor
4320 Views

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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