In biology, the inner lining of tubular structures is called a lumen.
This can refer to numerous tubular structures in the body, such as the lumen of the veins and arteries, the lumen of the intestines or the tubes in the kidneys.
This term can also be used to describe a space defined by membranes of cell organelles such as the lumen of the mitochondria, the Golgi apparatus, and others.
The scientific investigation is the systematic approach of the scientists to answer the questions about the world. It is applied almost all of the theories including the Theory of Natural Selection. Darwin's theory of evolution is a result of scientific investigation. In this theory, they investigate by observing the distribution of species.
D, I’m assuming that’s their is a another so you give on group nothing and the other group the vitamin C
Blood is just red.
Blue blood in diagrams is just used to distinguish between deoxygenated and oxygenated blood but there’s no such thing as hving blue blood.
