Factors Affecting the Rate of Diffusion
Size
Small molecules can slip by the polar heads of the phospholipids and through the membrane to the other side. Oxygen gas, carbon dioxide and water can move in this manner. Very large molecules like proteins cannot diffuse across the membrane at all.
Shape
Glucose is able to get into cells much faster than other sugars. This is accomplished by facilitated diffusion. A carrier protein specific for glucose (not other sugars) combines with it on the outer surface, closes around it, and then opens to the inside of the cell where the glucose is released. The carrier then returns to its original shape and is ready to transport another glucose molecule. These carriers can move up to 100 glucose molecules per second across the cell membrane.
Concentration
The greater the concentration gradient between the outside and inside of the membrane the greater the rate of diffusion. If the concentration of oxygen outside the cell increases then it will diffuse more quickly into the cell. The opposite is also true. If a muscle cell for example is working hard and using up large quantities of oxygen in cellular respiration producing ATP, then the low levels inside the cell will increase the concentration gradient compared to outside and the rate of diffusion of oxygen into the cell will increase. The same conditions in a muscle cell would create high concentrations of carbon dioxide inside the cell and increase the rate of diffusion from inside to outside.
Charge (+/-)
Ions or molecules with a charge cannot pass through the lipid bilayer by diffusion. Other mechanisms involving protein carriers and ATP energy are required. The sodium/potassium ion pump is an example of this type of transport.
Lipid Solubility
Lipid soluble molecules can move through the lipid bilayer. Generally these molecules are other lipids. Steroid hormones like testosterone and estrogen are examples of such molecules. This easy access to cells explains the powerful and wide ranging effects of such hormones.
Temperature
In general, increases in temperature cause all molecules to move faster. Diffusion is a passive movement of molecules so quicker molecule movement translates into quicker diffusion.
Rate of diffusion increases as: * Diffusion distance decreases * Concentration gradient increases * Surface area increases
There several physical factors that affect the rate at which particles diffuse. These include: the size of the particle, the temperature, the concentration difference, the diffusion distance, the surface area, and permeability.
The concentration difference and the temperature !
1. Size of particles
2. Concentration gradient
3. Temperature
4. Surface area
distance and the material through which diffusion is occurring (each material has a diffusion coefficient).
Temperature is one of them. Cold slows it.
gravity, mass, and density
Consintration temperature and pressure
Temperature
Steepness
Factors affecting the rate of reaction 1. Temperature 2. Catalyst 3. Concentrations of the reactants 4. Nature of the reactants 5. Surface area of the reactants
The factors affecting Perth's climate are distance from the sea, prevailing winds and latitude.
Deforestation, Irrigation and Urbanisation.
factors that affect the rate of mechanical weathering?
the sun and air pressure
There several physical factors that affect the rate at which particles diffuse. These include: the size of the particle, the temperature, the concentration difference, the diffusion distance, the surface area, and permeability.
the factors which affect rate of diffusion is the factors that mixing one substance to another.
stomatal movements( it depends on light, temperature, condition of the plant, glucose & sucrose concentrations, ion concentrations....) , intra cellular gaps in spongy paranchyma, atmospheric & plant pressure, amount of gases in the atmosphere, ...... are the factors which effect the gas exchange.
temperature and time.
Two factors which determine the rate of diffusion of a liquid in another liquid include temperature and particle size. The higher the temperature, the faster diffusion takes place, and the smaller the particle, the faster diffusion takes place.
C. Christoforou has written: 'The factors affecting adoption and diffusion'
Relative advantage, compatibility, observability, trialability and complexity
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factors that affect dissulution process?
Diffusion refers to the process where substances from a highly concentrated area move to a place with a lower concentration. The three factors that affect the rate of diffusion are temperature, concentration gradient and the molecular weight of the substances.
Diffusion rate varies with concentration difference, temperature and dimension of transfer path (area or distance).
consistecy feed rate