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.
Asexual reproduction involves only one parent and the offspring is identical to the parent. An example of an organism that reproduces asexually is Archaea or bacteria. Sexual reproduction involves two parents and the offspring's genes are equally contributed by each parent. An example of organisms that reproduce sexually are some land mammals. The chromosomes of a parent and offspring in asexual reproduction are identical and there is no difference in the chromosomes.
Answer:
Meiosis produces four genetically different haploid cells.
Gametic chromosomes have a different combination of alleles than parental chromosomes as a result of independent assortment
Explanation:
Meiosis and Mitosis are two types of cell division that occurs in living organisms. However, Mitosis produces daughter cells that are genetically identical to the parent cell while meiosis produces daughter cells that are genetically different from the parent cell. This accounts for the reason meiosis leads to genetic variation.
The production of genetically different cells by meiosis is as a result of the process of the random orientation of chromosomes during metaphase I of meiosis I. This process is called INDEPENDENT ASSORTMENT. However, crossing over occurs during prophase I of meiosis between non-sister chromatids of homologous chromosomes.
Answer:
So blood can reach the fetus
Explanation:
