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Compare and contrast the features of eukaryotic DNA and RNA

Both DNA and RNA a nucleic acids, made up of nucleotides, that encode genetic information. A nucleotide is a molecule composed of phosphate, sugar and a base, and these nucleotides bind to one another to for...
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Answered by Sophia A. • Biology tutor
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How do populations of bacteria develop antibiotic resistance?

There is VARIATION amongst the population due to naturally occuring MUTATION during DNA replication . The antibiotics act as a SELECTION PRESSURE, so only the bacteria with the allele for antibiotic resistan...
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Answered by Leila G. • Biology tutor
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What endocrine glands regulate sexual activity in males? How does this regulation work and what hormones are involved?

Here are the endocrine glands that regulate sexual activity in males: 1) the hypophysis (aka. the pituitary); 2) the adrenal glands; 3) the gonads (testicles). - - - - - - - - - - - - - It's pretty much all ...
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Answered by Lydia T. • Biology tutor
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During the cardiac cycle , there is a delay between the excitation of the atria and excitation of the ventricles. Explain how this is achieved and why this delay is essential.

Excitation from SAN (sino-atrial node) spreads across atria , causing them to contract first. The excitation is conducted to the AV (atrio-ventricular) node, which introduces a 0.12s delay . This refractory ...
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Answered by Jane E. • Biology tutor
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How does a signal move from one neurone to another and how does this process change for different motor responses?

The transmission of an action potential- the signal- from one neurone to another occurs over the synapse. The structure of a synapse is as follows; there is a presynaptic bulb, a post synaptic bulb and the s...
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Answered by Amy H. • Biology tutor
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