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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...
AB
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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