There are 23 pairs of chromosomes in each cell in a normal adult human.
<em>Direct </em><em>Contact</em><em> </em><em>Infection</em>
<em>Direct</em><em> contact are touching, kissing, contact with oral secretions, or contact with body lesions.</em>
<em>Hope</em><em> </em><em>it</em><em> </em><em>helps</em><em> </em><em>（⌒▽⌒）</em><em>（⌒▽⌒）</em>
<u>Answer</u>:
The organic chemicals that helps cell membranes to conserve the internal fluids are phospholipids.
<u>Explanation</u>:
Phospholipids are used to form plasma membrane of the cell. Plasma membrane surrounds the cell contents like various cell organelles, nucleus, ribosomes and proteins. A phospholipid molecules is made up if a polar head containing a phosphate group and the two non-polar tails made of long chains of hydrocarbon of fatty acids.
The another name for plasma membrane is phospholipid bilayer. The polar head is hydrophilic that interactes with polar environment while facing outside the bilayer while the non-polar tail is hydrophobic in nature which makes the internal hydrophobic region of cell membrane which faces inside the bilayer.
