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The nucleus contains genetic material which controls the activities of a cell
A vaccine contains a dead or inactive (an therefore harmless) form of a pathogen. By injecting this into the body, an immune response is triggered and white blood cells produce antibodies specific to the ...
So when we give an antibiotic (a drug that kills bacteria) it will kill all of the bacteria that are sensitive to it, if it's taken correctly. A few bacteria may have an adaptation allowing them to resist...
When it’s too hot, vasodilation occurs, in which the capillaries near the surface of the skin increase in diameter, allowing more blood to flow through them, releasing heat. Hairs on the skin lie flat. Th...
Leaves have a large surface area so more light hits them. The upper epidermis of the leaf is transparent, allowing light to enter the leaf. The palisade cells contain many chloroplasts which allow light t...
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