Answer:
Its Electrons; as you move down they stay the same
Explanation:
Where's the evolution?
The physics of light affects not just how blue water looks to us, but how the animals living in the world's oceans, lakes, and rivers are able to find food and each other — and this, in turn, can impact their evolution. Natural selection favors traits that perform well in local environmental conditions. Many fish species, for example, have evolved vision that is specifically tuned to see well in the sort of light available where they live. But even beyond simple adaptation, the physics of light can lead to speciation. In fact, biologists recently demonstrated that the light penetrating to different depths of Africa's Lake Victoria seems to have played a role in promoting a massive evolutionary radiation. More than 500 species of often brightly colored cichlid fish have evolved there in just a few hundred thousand years!
Answer:
False
Explanation:
The blood brain barrier (BBB) is a selective border that prevents the entry of foreign substances into the brain. It is made up of different components including endothelial cells, astrocytes, and pericytes etc.
Of all these mentioned three, the endothelial cells are directly responsible for the selectivity of the BBB. The endothelial cells are bound together by the tight junctions situated between them, impeding the passage of foreign materials e.g. solutes, pathogens etc.
Astrocytes help to maintain the BBB by surrounding the endothelial cells, providing biochemical strength.
The pericytes are located in the basement membrane, where they communicate with endothelial cells. They help to sustain the BBB by stabilizing and monitoring the maturation of endothelial cells via communicating directly between cell membrane as well as paracrine signalling.