The respiratory system is separate from the circulatory system. It is a complex network of tubes that delivers oxygen-containing air to every cell of the body.
Answer: tracheal tubes
Coal creates a negative impact on the environment because it contains sulfur and other harmful elements. When you burn coal these elements are then released into the air. And it can cause air pollution and health dangers as it releases a lot of carbon dioxide.
The difference between protons and neutrons are that one has a positive charge and one has a neutral charge. The similarities between the two is that they both make up an atom. The Electrons in an atom are in orbit of the cell inside the Electron cloud and is kept in the cloud by electromagnetic force.
1. PbO is a possible formula units, since O has charge of 2- and Pb can have a charge of 2+ or 4+, if it uses the 2+ ion, the charges will balance out to form PbO. Li+ and B(3-) would have Li3B, Al(3+) and Pb(2+) are both positive charges and would not balance out, Cl- and O(2-) are both negative charges and would not balance out.
2. Iodine is a halogen, so it has a charge of -1. Calcium is an alkaline earth metal in Group 2, so it has a charge of 2+. Therefore, if they were to form a formula unit, the resultant would be CaI2 (2 iodine atoms of 1- charge are needed to balance out the 2+ charge on the calcium atom).
3. Strontium is an alkaline earth metal with a charge of 2+, while phosphorus has a charge of 3-. Therefore, to balance the charges out, we would need 3 atoms of strontium and 2 atoms of phosphorus. This would give the formula unit of Sr3P2.
Answer:
d. tissue
Explanation:
There are several levels of organization of life which starts from the functional unit of life called cell.Cells are made of a combination of macromolecules that consist of atoms. Several cells associate together to perform one or more specific functions at the tissue level. The tissue level is made up of similar cells that carry out similar task or functions. The robot’s cardiac cells that work together in synchrony could be considered at the tissue level.