I would say D! Purely because it is looking at the effects of humans (therefore related to topics more geographical).
Hope that helps. :)
Answer:
It is pertinent to understand what hypertonic, hypotonic, and isotonic solution means before setting out to explain how a cell reaches equilibrium in each type of solution.
A hypertonic solution is one whose solute concentration is higher than that of the sap of a cell that is immersed in it.
A hypotonic solution is one with the same solute concentration as that of the sap of the cell immersed in it.
An isotonic solution has a lower solute concentration than that of the sap of the cell immersed in it.
In biological systems, water molecules move by osmosis from the region of higher water potential or lower concentration of solutes to the region of lower water potential or higher concentration of solute. An equilibrium is reached when there is no net movement of water between two sides. Hence;
A cell placed in a hypertonic solution will lose water to the surrounding solution until an equilibrium is reached. This means that such a cell will end up shrinking (wilting) or even dying due to loss of water from the cell sap.
A cell placed in a hypotonic solution will gain water from the surrounding solution until there is no net movement of water anymore. Such a cell might become turgid or even burst out its cell content.
A cell placed in an isotonic solution will neither gain nor lose water because the cell sap and the surrounding solution have equal solute concentrations.
Explanation:
The answer is an envelope.
A virus is an infectious agent that can replicate only inside a host cell. When it is outside the cell, it consists of genetic material coated with protein capsid. Some viruses also have an envelope which covers capsid. The function of the envelope is to identify and bind some receptor sites on the host membranes. After fusing with the cell membrane, it allows to capsid and genetic material to enter the cell and infect it.
Answer:
The North produced 17 times more cotton and woolen textiles than the South, 30 times more leather goods, 20 times more pig iron, and 32 times more firearms. The North produced 3,200 firearms to every 100 produced in the south
