Answer:
The cell contains a nucleus
Explanation:
in the early atmosphere, the earth had no trees, and the gases were mainly, carbon dioxide, methane and nitrogen. no oxygen.
when plants began appearing, it increased oxygen in atmosphere, and decreased carbon dioxide, which was also dissolved into oceans forming within sedimentary rocks.
this increase in oxygen continued, and helped create human life.
Answer:
rising temperatures, droughts, shifting patterns of precipitation and longer growing seasons, plants and animals are evolving to keep pace. Biologists have observed squirrels and salmon developing at an accelerated pace, causing them to reproduce at a younger age.
The white blood cells maintain homeostasis in the body as they protect it from different pathogens. They protect the body from different viruses, bacteria, etc. and keep it healthy.
Blood is the combination of both cells and plasma; the cell parts consist of red blood cells, white blood cells, and platelets. The red blood cells play an important role in gas exchanges and keep the cells oxygenated.
The white blood cells consist of lymphocytes such as B lymphocytes, T lymphocytes, macrophages, eosinophils, basophils, neutrophils, etc. All these cells play an important role in the body's immune system. The neutrophil is the first to go to the site of infection, followed by macrophages. The B and T lymphocytes are adaptive immune cells, and they get activated after they come across the pathogens. The platelets are responsible for the blood clotting; they stop the blood loss.
Hence, in this way, the white blood cells regulate the body's immunity by encountering pathogens and maintaining homeostasis.
Find out more about blood here.
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