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Describe the process of ventilation, including the difference between active and passive expiration.

To expand the lungs and fill them with air, thoracic pressure decreases. This is done by the diaphragm contracting and flattening out and the external intercostal muscles raising the ribcage upwards and outw...
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Answered by Steph G. • Biology tutor
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How do fish ventilate their gills?

Unlike mammals fish have water as their gas exchange medium instead of air. Fish use gills for gas exchange, gills are specialised flaps of tissue which have the following features to allow efficient gas exc...
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Answered by Meg H. • Biology tutor
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Explain the cardiac cycle

basic anatomy of the heart: chambers, valves, structural difference between right and left side of the heart pulmonary vs. systemic circulation blood flow through the heart
UT
Answered by Umamah T. • Biology tutor
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Describe the differences between mitosis and meiosis and when would these occur in mammalian cells?

Both mitosis and meiosis use cytokinesis for the division of genetic informaton between cells, however mitosis creates identical copies known as daughter cells after just one round of cell division, whereas ...
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Answered by Aimee D. • Biology tutor
3317 Views

Name the three components that make up a nucleotide

First of all a nucelotide is the monomer that makes up DNA. Millions of monomers are joined together to form the double helix of a DNA molecule. A nucleotide is made of a pentose sugar (in the case of DNA th...
AS
Answered by Amy S. • Biology tutor
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