A primary air pollutant is directly from the source and secondary pollutants are omitted from two or more different primary pollutants interact with each other in the atmosphere.
EX of primary: carbon monoxide, nitrogen oxide, sulfur oxid
EX of secondary: NO2 acid rain
I believe it’s C because the heart pumps blood through the body
<span>Men can produce sperm throughout their adulthood because their reproductive organs and glands are fully developed. During their childhood and adolescence the glands and organs are not functional for reproductive purposes.</span>
Organisms can be made up of many<em> </em><u>cells</u>, which could be arranged into <u>tissues</u> which can make up<u> organs</u>, organs can be part of a(n)<u> system</u>. These are........i don't really know after this since you didn't give a lot to work with and i'm not even sure if this is right or not lol.
Answer:
Either the cell wall or the cell membrane.
Explanation:
All cells have cell membranes which line the outside of the cell, and some cells have cell walls, which also line the outside of the cell. Since all cells have cell membranes I am inclined to believe that the correct answer would be cell membranes.
