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Describe how mRNA is produced in a cell (5 marks)

Double-helix DNA strands are separated by breaking the hydrogen bonds between complementary bases. One strand acts as a template strand which complementary bases bind to (adenine to uracil, thymine to adenin...
SG
Answered by Shubham G. • Biology tutor
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Describe how the cells formed by meiosis are different from the cells formed by mitosis

During mitosis a cell undergoes DNA and organelle duplication followed by a single division, each haploid daughter cell produced this way is genetically identical to the parent cell. In contrast to this meio...
MB
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When a nerve impulse arrives at a synapse, it causes the release of neurotransmitter from vesicles in the presynaptic knob. Describe how.

The arrival of a nerve impulse at a synapse causes Ca2+ channels to open (1 mark). Ca2+ ions enter the presynaptic knob by facilitated diffusion (1 mark). The presence of Ca2+ ions causes synaptic vesicles t...
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Answered by Andrew B. • Biology tutor
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Explain the differences between enzyme inhibitors

There are two types of inhibitors. Competitive inhibitors have a similar tertiary structure to the substrate and so can bind temporarily to the enzyme’s active site. This blocks the active site meaning the s...
LN
Answered by Laura N. • Biology tutor
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Compare and Contrast Meiosis and Mitosis

Similarities: Types of cell division which take place in Eukaryotic cells Differences: Meiosis - Occur in sex cells to produce haploid daughter cells; non-identical; recombination in order to produce genetic...
LA
Answered by Lydia A. • Biology tutor
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