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What is osmosis and how does it differ from what I learned at GCSE about diffusion

At GCSE osmosis was simplified to just diffusion of water so it is the spreading out of water molecules from where there is a high concentration to a low concentration- but in fact osmosis depends both on th...
KG
Answered by Katie G. • Biology tutor
6887 Views

Explain how the DNA of a Eukaryote is replicated

To replicate the DNA of a eukaryotic cell, the double helix structure must first be unwound to present the base pair sequence. This is done using DNA helicase (this enzyme breaks the hydrogen bonds connectio...
OW
Answered by Oscar W. • Biology tutor
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Highlight 3 differences between mRNA and DNA molecules

mRNA is only single stranded, whereas DNA is a double stranded molecule 2. mRNA has Uracil instead of thymine which is found in DNA 3. mRNA contains no introns as they have been spliced out, however DNA cont...
SA
Answered by Safia A. • Biology tutor
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Why do humans have a double circulatory system?

Ask the student: what other option is there? What are the differences between the two? Answer: Humans have a small surface area to volume ratio, so diffusion alone is not enough to meet the high metabolic de...
DV
Answered by Divya V. • Biology tutor
9504 Views

How do I explain the process of Natural Selection?

VOSSAG V - Variation: all organisms undergo varying amounts of genetic variation due to genetic mutations or environmental factors (such as geographic separation). O - Overpopulation: all populations have th...
BK
Answered by Ben K. • Biology tutor
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