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White blood cell

White blood cells (also called leukocytes or immune cells) are cells which form a component of the blood. They help to defend the body against infectious disease and foreign materials as part of the immune system. There are normally between 4x109 and 11x109 white blood cells in a litre of healthy adult blood - about 7,000 to 25,000 white blood cells per drop. In conditions such as leukaemia this may rise to as many as 50,000 white blood cells in a single drop of blood. As well as in the blood, white cells are also found in large numbers in the lymphatic system, the spleen, and in other body tissues.

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August 16, 2025

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A study finds that people are more open to plant-based eggs when they’re part of familiar foods, like pancakes, rather than served plain. While taste and appearance still favor regular eggs, vegan eggs score higher on environmental and ethical ...
A six-month randomized trial challenges the idea that eating more sweet foods increases a person’s preference for sweetness. Participants on diets with high, low, or mixed sweetness levels showed no changes in their sweet taste preferences, energy ...
Researchers have discovered that parts of the human brain age more slowly than previously thought—particularly in the region that processes touch. By using ultra-high-resolution brain scans, they found that while some layers of the cerebral cortex ...
Scientists have discovered a direct cause-and-effect link between faulty mitochondria and the memory loss seen in neurodegenerative diseases. By creating a novel tool to boost mitochondrial activity in mouse models, researchers restored memory ...

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