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What is the 'lagging strand' in DNA replication, and how is it different from the 'leading strand'?

The lagging strand in DNA replication is the strand of the double-stranded DNA molecule that has to be synthesised discontinuously. This is because the two strands of DNA molecules are antiparallel, so run i...
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Answered by George R. • Biology tutor
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I know all the theory, but I can never score well with the essay questions in paper 2. Why?

As you've probably noticed, the mark scheme is incredibly specific about the terminology that you use. You could describe the process of, say, endocytosis, to great accuracy, but if you don't use the exact k...
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Answered by Amy W. • Biology tutor
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Explain how proteins act as enzymes, including control by feedback inhibition in allosteric enzymes [9 marks]

The following answers this past exam question. Test your understanding by defining all the CAPITALISED words. Enzymes are GLOBULAR PROTEINS, which contain an active site to which the substrate binds. The sha...
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Answered by Paulien S. • Biology tutor
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What evidence is there for evolution?

For IB Biology, there are three types of evidence for evolution you need to know: fossils, selective breeding and homologous structures. Fossils are preserved remains or traces of organisms from the past – t...
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Answered by Emma F. • Biology tutor
11161 Views

How can different phenotypes be generated without changes to the genotype?

Different phenotypes can be generated without changes to the genotype through a process called Epigenetics. Epigenetics, meaning “above genes”, is the study of changes to the phenotype caused by changes in g...
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Answered by Ana D. • Biology tutor
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