Answer:
The immune system protects the host from pathogenic organisms (bacteria, viruses, fungi, parasites). To deal with this array of threats, the immune system has evolved to include a myriad of specialised cell types, communicating molecules and functional responses.
Explanation:
The iris I the first part of the eye that light hits.
Answer:
Scientist count the world humans population with an organization called The United Nations Population Division (UNPD),
Explanation:
Which keeps track of the world population, projects that the world's human population will hit 7 billion on Halloween Day 2011. Admittedly, that is just an estimate: There's no way to know exactly how many people are alive at any given moment, and the true date that humanity's ranks will surpass 7 billion could come in the weeks or months before or after Oct. 31. Nonetheless, the UN's guess is the best there is.
Answer:
A I think sorry if its wrong
The tiny blood vessels that are responsible or have the role
of transporting absorbed nutrients in our body is the capillaries. It is a network
in which connects the venules and the arterioles in order to transport and
connect nutrients for evenly distribution in the body.