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What causes an unsaturated fatty acid to have a different shape than a saturated fatty acid? o a. unsaturated fatty acids have more hydrogen atoms. o b. unsaturated fatty acids have double carbon bonds. o c. unsaturated fatty acids have more nitrogen atoms. o d. unsaturated fatty acids have single carbon bonds.

What are antigens and antibodies? how are they involved in the body’s response to incompatible blood?

This is a biological reaction due to a stimulus. i need this quickly !