Humans' internal body temperature is a great example of homeostasis. When an individual is healthy, his or her body temperature retains a temperature 98.6 degrees Fahrenheit. The body can control temperature by making or releasing heat.
        
             
        
        
        
<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.
 
        
             
        
        
        
<u>Answer:</u>
The series dilution method is the step wise dilution technique where the dilution factors remain constant in each step.  
The advantages of using the series of dilution method over simple dilution are stated below: 
<em>a)        Aids in reduction of a dense culture of cells to a more usable concentration.</em>
<em>b)        In every step of dilution the specific amount of bacteria is removed. </em>
<em>c)        Helps in the estimation of concentration of an unknown sample.</em>
<em>This sums up the advantage of using the series dilution technique.</em>
 
        
             
        
        
        
Synthesis of a protein destined to function in the nucleus occurs AT THE RIBOSOMES. 
Proteins are synthesized in the ribosomes. Newly synthesized proteins that are meant for the nucleus usually possess a localization sequences which direct it to a protein on the nuclear membrane through which it will enter into the nucleus.<span />
        
             
        
        
        
<span>A. Exact ecological footprints are often difficult to calculate, but estimates can be useful in comparing populations.
</span>Which of the following could be said about ecological footprints? <u /> <u>Exact ecological footprints are often difficult to calculate, but estimates can be useful in comparing populations.</u><u />
NOT:
b. Ecological footprints can't be used to determine carrying capacity.
C. Ecological footprints don't take into account resources needed to absorb and manage wastes.
<span>D. The average ecological footprints for various countries are nearly identical.</span>