Answer:
2. cell wall
Explanation:
The Cell wall is a thick layer made up of peptidoglycan that structurally supports and protects the cell. The cell wall is located just outside the semi permeable membrane. It give rigidity to the cell.
The cell wall also serves as a sieve or filter that allows or prevents the movement of molecule in or out of the semi permeable membrane.
An hypotonic solution is a solution that has a higher quantity of water when compared the quantity of solute dissolved in the water and this causes the solution to have a lower osmotic potential. 
When a bacteria is growing in an hypotonic surrounding environment, there is a large amount of water present outside the cell. The cell wall of the bacteria serves as barrier and prevents the flow of water into the cell and this would prevent the cell wall of the bacteria from bursting open due to the rigidity of the cell wall.
Any bacteria that lacks a cell wall and is place in an hypotonic surrounding environment would swell and eventually burst open due the movement of water from hypotonic surrounding environment into the bacteria.
 
        
             
        
        
        
Answer:
d. As depth increases, temperature decreases quickly at first, but eventually becomes constant.
Explanation:
As seen on the graph above, the<em> temperature decreased quickly as the depth increased</em>. It is seen between <u>200 meters to 500 meters</u> in depth. The change in temperature is from <em>26 degrees</em> to <em>8 degrees</em>, which is<em> </em>an<em> 18-degree difference. </em>After which, the temperature decrease<em> slows down </em>and becomes <u>constant</u> starting at <em>2,700 meters</em> going deeper to <em>4,000 meters. </em>The temperature is being maintained at <em>1 degree</em>.
The other three choices above<em> (a, b, and c) s</em>how <u>both an increase in temperature with an increase in depth</u>. <em>This makes the choices incorrect.</em>
 
        
                    
             
        
        
        
The heart pumps blood through the pulmonary and systemic circuits of the circulatory system. 
In humans, the blood flows from the heart in two circuits or paths. The pulmonary circuit allows blood to flow between the heart and the lungs, while the systemic circuit allows blood to flow between the heart and the rest of the body. 
The right side of the heart pumps deoxygenated blood to the lungs through the pulmonary circuit to oxygenate the blood. The oxygenated blood returns to the heart and is pumped by left side of the heart through the systemic circuit to oxygenate the rest of the body. Then, blood becomes deoxygenated as is passes through the body. The deoxygenated blood from the body flows back into the heart via the systemic circuit. The deoxygenated blood onces again moves through the pumonary circuit for oxygenation and the cycle begins again.