The Alveolar macrophages, Cilia and the mucus layer
I think its called the <span>doldrums. I had a friend who lived in Africa on the equator and i remember her mentioning this (this was also in 2007, so dont quote me here lol)
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Air must pass from the back to the front of the pharynx to enter the trachea and food must pass from the front to the back of the esophagus
Three scientists are credited with the development of cell theory. Matthias Schleiden observed that all plants were made of cells; Theodor Schwann observed that all animals were also made of cells; and Rudolf Virchow observed that cells only come from other cells.
Protein plays a crucial role in almost all biological processes and amino acids are the building blocks of it. A large proportion of our cells, muscles and tissue is made up of amino acids, meaning they carry out many important bodily functions, such as giving cells their structure