A decrease in the population of bears
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Answer:
D. Microglia
Explanation:
Microglia are phagocytic, which means that they are cells that can engulf other cells and particles. Microglia protect the CNS by engulfing foreign particles and bacteria. They act also as a clean-up crew that help remove dead cells. They are found in both the brain and spinal cord, which make up the Central Nervous System, or the CNS.
Stone tools we’re first used around 3,300 BCE
The answer is; D
The angle at which the sun rays strike the earth at the equator is more or less 90 degrees while you move towards the poles, it much less than this. This means that the unit of sunlight per surface area received at the equator is higher than that at the poles. This is why the equator is always warmer than the poles.