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.
Almost everything imaginable pollutes the water, whether it be plastic cans or dumping beverages into the ocean
The sequence of amino acids in a protein is determined by DNA. In a protein that is present in all species, the amino acid sequence will be different. Once a protein has been chosen, the amino acid sequence of that protein in different species are compared. More similarities, or fewer differences, indicate that two species are closely related. (sorry if im wrong!)
The assortment of homologous chromosomes during meiosis is random and generates genetic variation, the raw material for evolution.
During metaphase I of meiosis, homologous chromosomes are lined up at the equator plate of the cell in order to be separated (assorted) in anaphase I.
The separation of homologous chromosomes during meiosis I is random. Daughter cells receive unique gene combinations from an original parent cell.
Subsequently, haploid cells got from two successive meiotic divisions fuse during fecundation to form a diploid (2n) zygote.
During prophase I, non-sister chromatids interchange genetic material by a process known as recombination. This genetic process also increases genetic variation in daughter cells.
In conclusion, the assortment of homologous chromosomes during meiosis is random and generates genetic variation.
Cold air usually pushes warm air because cold air has a HIGHER DENSITY
