Answer:
A. pH
Explanation:
Denaturation of proteins is a protein whereby the protein molecule loses its primary structure and ultimately its physical functioning as a result of factors including pH, temperature or concentration of chemicals. Based on this definition, it is visible that denaturation of proteins can be caused by these three factors: pH, chemical and temperature.
However, in this case of PEPSIN enzyme, which is a proteinous molecule produced in the stomach of humans and functions in breaking down proteins, its denaturation occurs as it moves along the digestive tract to the intestines. This is as a result of the changes in pH in the digestive tract.
The pH of the stomach where pepsin is produced is acidic i.e. <3.0. However, as one moves towards the intestine, the pH increases, which is unfavorable or considered harsh for the pepsin enzyme. Hence, it gets denatured.
a process by which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one, thus equalizing the concentrations on each side of the membran.
Answer:
A phospholipid
a. has both polar and nonpolar regions.
Explanation:
Phospholipids, as amphipathic molecules, consist of a glycerol molecule, two fatty acids, and a phosphate group that is modified by an alcohol. The phosphate group is the negatively-charged hydrophilic (water-loving) polar head, which face outward and are attracted to the intracellular and extracellular fluid. The fatty acids are the uncharged, hydrophobic (water-fearing) nonpolar tails, which face the inside, away from the water and meet in the inner region of the membrane.
Cells are the basic structural, functional, and biological unit of all known living organisms. Cells of various types have different functions but the generalized cell functions include movement of substances across the cell membrane, cell division to make new cells, and protein synthesis. So, the answer is D, cell can conduct many tasks, including duplicate themselves, convert energy and selectively exchange materials.
