Answer:
<h2>C. placing carrier proteins in the membrane.</h2>
Explanation:
If there is no barrier preventing molecules from moving molecules, then there will be large movement of molecules from an area of high concentration to an area of low concentration. This passive process is known as diffusion. The phospholipid bilayer of a cell's membrane works as a barrier to large molecules, ions, and most hydrophilic molecules. Whereas small hydrophobic molecules can pass freely through the phospholipid bilayer, other molecules and ions are transported across the cell membrane with the help of transport proteins. Some transport proteins, allowing hydrophilic molecules and ions to passively move through them and across the cell membrane.
Examples: carrier proteins and channel proteins.
Placing carrier proteins in the cell membrane will allow the molecule to reach equal concentrations on the both the sides of the membrane and maintain that way over long time. In contrast, transport proteins known as pumps will use cellular energy, usually in the form of ATP, to transport molecules.
Placing equal numbers of intracellularly directed and extracellularly directed pumps would also equalize the concentrations of a molecule long over time. Pumps are to transport molecules against their concentration gradient, such as the sodium-potassium pump continuously moves sodium ions out of a cell.
Through the use of carrier proteins, there is equalization of concentrations of a hydrophilic molecule. This equalize the numbers of molecules on the inside and outside of the cell, but the pumps would continue moving the molecule inward, eventually resulting in more molecules inside of the cell than out.
Answer:
The correct answer is desert-dwelling species.
Explanation:
Any preserved remains, trace or impression of anything, which was once living in the past is termed as a fossil. The examples of fossils comprise stone imprints of microbes or animals, bones, exoskeletons, shells, coral, remnants of DNA, the substances getting preserved in amber, and others.
For the formation of fossils, the most essential condition is decomposition that takes place gradually, that is, at a slow pace. Thus, places like wet marshy areas will be the locations where the maximum of the fossils can be found as such places provide optimum conditions for slow mineralization and decomposition of bones.
On the other hand, places like deserts would be the least likely to have a fossil record as deserts are devoid of optimum conditions required for the formation of fossils. In places like a desert, decomposition and demineralization of the components like bones take place at a brisk rate.
Answer:
Osmosis occurs until the concentration gradient of water goes to zero or until the hydrostatic pressure of the water balances the osmotic pressure. Osmosis occurs when there is a concentration gradient of a solute within a solution, but the membrane does not allow diffusion of the solute.
Explanation:
<span>The graph portrays
predation. The relationship shows that an
increase in the population of zebra
results in a subsequent increase in the lion population, and vice versa. This,
therefore, means that the lion population
is dependent on the zebra population due to an interaction (predation). The lion population
will always be lower than that of the zebra because of the inefficiencies of energy transfer up the trophic levels (exhibited by a
typical energy pyramid). </span>
