Question

1. Movement of fluids through a selectively permeable membrane caused by hydrostatic pressure is referred to as ____________ .

2. The pressure exerted by a fluid on the inside wall of its container (or vessel, in the case of the human body), is called ____________ .
3. The movement of particles from an area of high concentration to an area of low concentration describes ____________ .
4. Movement away from high solvent concentration or towards high solute concentration describes ____________ .
5. The movement of small, polar molecules across the plasma membrane by a carrier protein is called ____________ .

Answer 1

1. FILTRATION

2. HYDROSTATIC PRESSURE

3. DIFFUSION

4. OSMOSIS

5. FACILITATED DIFFUSION

Step-by-step explanation:

1. Filtration is a variation of diffusion. It is the movement of a material according to its concentration gradient through a semi-permeable membrane. This movement is facilitated and enhanced by an osmotic or hydrostatic pressure, causing the substances to filter more rapidly. A typical example of this process is in human excretion, where the kidney forces large amount of water and dissolved solutes out of the blood stream into renal tubules. The rate of this movement is dependent on the pressure formed by the concentration gradient.

2. Hydrostatic pressure is force exerted by an intravascular fluid (blood plasma) or extravascular fluid on its wall. It refers to the pressure exerted on the wall of a confined space by a fluid, due to the weight of the fluid (blood, in this case) above it. Hydrostatic pressure increases in proportion to depth measured from the surface because of the increasing weight of fluid exerting downward force from above.

3. Diffusion is the net movement of substances/particles from an area of higher concentration to an area of lower concentration until the concentration is equal. The movement occurs as a result of random and constant motion of all molecules, atoms, or ions. Since it occurs randomly, some molecules may be moving against concentration gradient while others may move across/down concentration gradient. The "net" indicated the overall and end result of the movement. Diffusion is a form of passive transport i.e. it involves movement of molecules down a gradient. Hence, it does not require energy.

4. Osmosis is the passive movement of water molecules from a region of lower solute concentration (higher solvent) to a region of higher solute concentration (lower solvent) through a selectively permeable membrane. A concentration can either be hypertonic (higher solute in solution than in cell), isotonic (equal solute in solution and cell) and hypotonic (lesser solute in solution than in cell). The direction of the movement of water is dependent on the concentration i.e. if a cell is placed in a hypertonic solution, water moves out of the cell, likewise, if please in a hypotonic solution, water moves into the cell.

5. Facilitated diffusion is the diffusion of polar and charged molecules through carrier proteins, called permeases, that are specific to one type of molecule in the plasma membrane. These materials are ions or polar molecules that are repelled by the hydrophobic parts of the cell membrane.This protein binds a substance and, in doing so, triggers a change of its own shape, moving the bound molecule from the outside of the cell to its interior. An example of protein channel is AQUAPORINS, which allows water molecules pass through the cell membrane. This process is also a passive transport and does not require energy.