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Explain the steps of action potential across an axon membrane?

Resting Potential-3 Na+ out, 2 K+ in.Action potential- A stimulus is detected causing Sodium voltage gated channels to open, leading to Na+ to flow into the axon and therefor making the inside less negative....
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Answered by Isabelle J. • Biology tutor
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Why is DNA replication semi-conservative?

DNA is in a double helix structure, meaning there are two strands. When we need DNA to replicate, for example when a cell divides during growth, the strands undergo unwinding. This process is done by an enzy...
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Answered by Emma C. • Biology tutor
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How are the alveoli adapted for gas exchange?

The alveoli are covered by a rich blood supply of capillaries- this provides a diffusion gradient for oxygen to move into the blood and carbon dioxide to move into the lungs.The alveoli are also highly folde...
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Answered by Fergus L. • Biology tutor
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Ella has just finished running a half marathon. She hasn't been drinking enough water so is dehydrated and is feeling incredibly hot. Describe how her body responds to these changes. (6)

She is dehydrated so osmoreceptors in the hypothalamus shrink, this causes ADH to be secreted by the pituitary gland. The ADH travels in the blood stream and acts on the collecting ducts of the kidney nephro...
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Answered by Natasha H. • Biology tutor
3309 Views

What is the difference between mitosis and meiosis?

Mitosis is the process used by normal body cells for everyday replication to maintain a healthy body, for example tissue regeneration. On the other hand, meiosis is the process whereby the gametes, sperm and...
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Answered by Clare G. • Biology tutor
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