A white blood corpuscle, shown here in red, attacks the yellow-coloured tuberculosis bacteria. The pathogens are encircled by the scavenger cell membrane, pulled into the interior of the cell, where ...
Inside you, there is an amazing network of blood vessels, the tubes that carry blood all around your body. Every part of the body needs oxygen, food and water. The blood vessels are a bit like ...
当前正在显示可能无法访问的结果。
隐藏无法访问的结果