Answer: the membrane channel
Explanation:
In passive diffusion, the small water molecules can move across the phospholipid bilayer seen in blue. This layer acts as a semi-permeable or selectively permeable membrane; its hydrophilic heads are attracted to water (seen facing outwards) while its water-repellent hydrophobic tails face towards each other- allowing molecules of water to diffuse across the membrane along the concentration gradient.
Thus the water will move from an area of high concentration to an area of low concentration, until the system reaches a steady state called equilibrium- after this, there will be no net movement of water. Similarly via osmosis, the water passes through the membrane due to the difference in osmotic pressure on either side of the phospholipid bilayer this means that the water moves from regions of high osmotic pressure/concentration to regions of low pressure/ concentration to a steady state.
The dialysis tubing mimics a semi permeable membrane; it only allows water and small molecules of iodine to cross into the bag containing starch. The tubing is impermeable to starch; these large molecules require the aid of protein omplexes called membrane channels, in order to move across the membrane and against the concentration gradient.
Answer:
The question to be asked an investigated when observing a structure under the microscope to determine whether it is living is if it has a nucleus if eukaryote or nucleoid if prokaryote.
Explanation:
The major organelle that must be present in all living cells is the nucleus or nucleoid and the protoplasm. The observation of the cell under the microscope will show the subcellular entity, nucleus/nucleoid, more pronounced than other organelles in the cell. The nucleus house the necessary information for the maintenance and reproduction, which is mainly the genetic information that dictates the translational protein products that are needed to build another aspect of the cells. Therefore, when such a tiny structure is placed under the light microscope under the view of oil immersion, the nucleus of the cell should be visible if it is a living structure.
Answer:
By far, the most abundant gas in the Earth's atmosphere is nitrogen, which accounts for about 78% of the mass of dry air.
Explanation:
The results clearly reveal that Imipramine is by far more effective than Lithium in preventing the recurrence of depression. 62.16% of the patients taking Lithium had a recurrence of depression which is more than twice that of patients who took Imipramine (28.95%).
The results also question the effectiveness of Lithium in general since the percentage of patients who had a recurrence of depression in the Placebo group (67.65%) is only slightly higher than that of the Lithium group (62.16%).
