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What are phagocytes and how do they protect the body?

Phagocytes are large irregularly shaped white blood cells that are involved in the non-specific immune system. They have the ability to engulf and digest foreign bodies, destroying them in a process known as...
AK
Answered by Atousa K. • Biology tutor
3618 Views

How does the presentation of a virus antigen by a macrophage lead to antibody production against the antigen?

T helper cells recognise and bind to the antigen and become activated. The activated T helper cell stimulate B cells to form plasma cells that produce and release antibodies that are specific to the viral an...
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Answered by Prakruthi P. • Biology tutor
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How does an action potential propagate?

a stimulus depolarises the membrane potential above the threshold level e.g. -40 mvthis causes voltage gated Na+ ion channels to open- resulting in an influx of Na+ into the cellthis depolarises the membrane...
SA
Answered by Syed A. • Biology tutor
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Describe the stages of phagocytosis (4 marks)

the phagocyte recognises the antigen on the pathogen surface as foreignThe phagocyte cytoplasm moves around the pathogen, and the membranes fuse, forming a phagosomeLysosomes containing lysozymes fuse with t...
AM
Answered by Aislinn M. • Biology tutor
11235 Views

Describe the process of DNA transcription:

The DNA double helix unravels as helicase breaks the hydrogen bonds between base pairs. RNA polymerase binds to the promoter region on the DNA strand. The RNA polymerase transcribes the DNA coding strand by ...
EC
Answered by Erin C. • Biology tutor
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