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Movement of solutes across a lipid bilayer plasma membrane can occur in many ways:
1. Osmosis: diffusion of water across membranes to balance solute concentrations.
- No energy req
- Water passes through membrane via aquaporins, pores in the membrane permeable only to water.
2. Simple diffusion: diffusion of only small, hydrophobic (nonpolar) molecules across a membrane down their concentration gradient.
- No energy req
- Only moves small nonpolar molecules down their concentration gradient
3. Facilitated diffusion (passive transport): uses transmembrane protein transporters (channels and carriers) to move polar molecules (ions) across a membrane
- No energy required
- Channel proteins: Allow for rapid diffusion of specific ions down their concentration gradient
- Can be activated by:
- Voltage
- Ligand
- Mechanical force
- Carrier proteins: Allow for selective diffusion of specific ions down their concentration gradient.
- Uniport carriers: only transport one specific ion down its concentration gradient
- Symport carriers: move two different types of ions in the same direction.
- Antiport carriers: moves two different ions in opposite directions
-Can use the energy created moving one molecule down its concentration gradient to move an ion against its concentration gradient
- Carrier proteins exhibit saturation, competition, and specificity.
4. Active transport: transport of solutes across a membrane against their concentration gradient.
- ATP req
- Uses carrier proteins
- Leads to creation of potential energy stored in electrochemical gradients
Wiki User
∙ 12y ago
Wiki User
∙ 9y agoThe simple diffusion of molecules occurs when molecules move away from each other in a gas or liquid. This is driven by the kinetic energy of molecules since they are in constant motion.
Wiki User
∙ 12y agowhat type of tissue is found where simple diffusion occurs
Wiki User
∙ 13y agoDiffusion occurs on the cell membrane.
Wiki User
∙ 14y agoit means the diffusion of the molecules.
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Which statement best describes the molecules made of carbon hydrogen?
Molecules made of carbon and hydrogen are various and diffuse. The best description is that they are hydrocarbons and they burn well.
What properties do liquid and gases have due to the movement of their molecules?
Liquids and gases are amorphous (shapeless), viscous (can flow), and diffuse (have internal space) due to the movement of their molecules.
How gas spreads?
The random motion of the gas molecules allows them to diffuse throughout the space available to them.
Would you expect the particles in chlorine gas to diffuse faster or slower than the particles in argon gas?
The rate of diffusion of a gas depends on the weight of the gas molecules. The heavier the molecules, the slower they move - the lighter the molecules, the faster they move. Nitrogen molecules weigh about 28 units. Chlorine molecules weigh 71 units. So we would expect nitrogen to diffuse more quickly than chlorine.
How did rice diffuse and where did it diffuse to?
my mom
What type of molecules diffuse?
All types of molecules
How do you use diffuse in sentence?
Oxygen molecules diffuse across the membrane.
Glucose is a molecule that can move across the cell membrane if the concentration of glucose is high or inside the cell than outside the cell then what will happen by the process of diffusion?
glucose molecules will diffuse out of the cell. apex
What kinds of molecules freely diffuse across a semipermeable membrane?
Water molecules freely diffuse across a semipermeable membrane.
Do molecules diffuse during equilibrium?
No.
What molecules diffuse out of a leaf?
Glucose
Why do sugar molecules not diffuse through a plant cell membrane?
The membrane is semi-permeable. Sugar molecules are too large to diffuse through.
Do all liquids diffuse the same way?
no because different molecules have different sizes. Smaller molecules will diffuse faster than larger molecules.
What determines how molecules are distributed in diffusion?
The concentration gradient is what causes molecules to diffuse.
How do molecules diffuse across membranes?
the reach equilibrium
What type of compound would easily diffuse into the cell?
A hydrophobic molecules (such as a steroid molecule) can easily diffuse into the cell
What things diffuse into?
The molecules of food and oxygen diffuse into cells. oh and btfw co2 and waste chemicals diffuse ut of cells. im in year 3
