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Explain how a blood clot can cause a heart attack?

A blood clot or thrombus is formed pathologically in the blood stream when the clotting cascade is activated inappropriately. This commonly occurs over the rough vessel surface during atherosclerosis of an a...
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Answered by Alex K. • Biology tutor
8819 Views

How does the kidney filter out different molecules?

In the blood flowing through the kidneys, you find lots of different substances, like glucose and amino acids (which the body wants to keep and use) and urea (which the body wants to get rid of). The first i...
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Answered by Isobel E. • Biology tutor
4658 Views

Explain how DNA replicates inside a cell

DNA is made up of 4 bases (Adenine, Thymine, Guanine, Cytosine) Adenine, guanine = purine 'Pure AGony' Thymine and cytosine = pyramidines Adenine pairs with thymine (2 Hydrogen bonds - '2 people know where i...
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Answered by Claire D. • Biology tutor
3961 Views

Describe the similarities and differences between simple diffusion, facilitated diffusion and active transport.

Simple diffusion, facilitated diffusion and active transport are three methods to transport various molecules across a membrane. Whilst similar in the overall effect, there are some major differences between...
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Answered by James G. • Biology tutor
83748 Views

Describe how the fluidity of the membrane and how this allows transport across it.

The fluidity of membranes allows it to invaginate and form vesicles. This is important for the process of endocytosis by which the cell is able to uptake materials from the extracellular environment. Vesicle...
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Answered by Naomi H. • Biology tutor
2816 Views