Exocytosis is ana ctive transport method and does not include any transport protein. whereas calcium ions pass through the membrane with the help of trans- membrane protein. These proteins make pores inside hydrophobic membrane and allow the ions to pass though it.
It is true that Urban sprawl covers land once used for food
production and destroys ecosystems. Many of the large cities that have come up
were once fertile lands for irrigation or were big jungles. These jungles were
cut down or the fertile lands destroyed to build cities and industries.
By the United States Census Bureau standards, a population
of 1000 people define an urban area is completely false statement. As per the
United States Census Bureau, more than 50000 people define an urban area.
Convection is the movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity, which consequently results in the transfer of heat.
The numbers 3 and 4 means that there are 3 Nitrogen atoms, and 12 Hydrogen atoms in the chemical formular (3NH4). The 3 coefficient in front of the compound applies to all of the elements while the 4 applies to only hydrogen (H). This means that the compound contains 3 Nitrogen atoms and 12 (4 multiplied by 3) Hydrogen atoms.