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1 a) What is a pathogen? 1 b) How do white blood cells help to defend the body against pathogens?

1 a) a microorganism that causes infectious disease 1 b) White blood cells: - Ingest pathogens - produce antibodies which destroy particular bacteria or viruses - produce antitoxins which counteract the toxi...
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Answered by Lauraa B. • Biology tutor
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What is diffusion?

All the cells in our body communicate constantly with their surrounding environment in order to feed and excrete their wastes. Various substances in that environment pass through the cell membrane to enter o...
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Answered by Kleio C. • Biology tutor
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How do mutations make non-functional enzymes?

Mutations are changes to the base sequence. The base sequence determines the amino acid sequence. A different base sequence therefore codes for a different amino acid sequence. Amino acids interact with each...
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Answered by Chris B. • Biology tutor
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How are signals transferred across a synapse?

The function of the synapse is to transfer electric activity from one cell to another. At chemical synapses, the presynaptic neuron is separated from the postsynaptic neuron by a synaptic cleft. Transmission...
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Answered by Caroline W. • Biology tutor
11467 Views

How do the structure of phospholipids contribute to their positioning in the cell plasma membrane?

The plasma membrane is organised into what is referred to as a lipid bilayer, consisting primarily of phospholipids and proteins. Phospholipids contain a hydrophobic (water hating) fatty acid 'tail' and a hy...
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Answered by Oluwatobi O. • Biology tutor
5622 Views