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A patient is infected by a pathogen. Explain the process of the imitation of the immune response (5 marks) The paitent was prescribed antibiotics yet their symptoms did not improve. What can you infer from this? (1 mark)?

5 of the following...
Pathogen has antigens on its surface that are recognised as foreign by the immune system
T helper cells stimulate cytotoxic T cells, B cells and phagocytes (or lysosomes)

Answered by Harriett F. • Biology tutor

2470 Views

What is the difference between catabolic and anabolic reactions? Give an example of a catabolic reaction you have studied.

In biology catabolic reactions are biochemical reactions during which an organic molecule is broken down. This process is usually involved in the production of energy. In contrast, anabolic reactions are...

Answered by Gabriele Z. • Biology tutor

2121 Views

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 negati...

Answered by Isabelle J. • Biology tutor

2849 Views

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 e...

Answered by Emma C. • Biology tutor

4889 Views

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 fo...

Answered by Fergus L. • Biology tutor

67837 Views