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There are three types of transport for molecules across the cell membrane.
1 - Diffusion - Molecules move from an area of high concentration to an area of low concentration
2 - Osmosis - same idea as diffusion, but refers to the movement of WATER across a selectively permeable membrane. How can you change water concentration? Add a solute. If you have 2 250 ml beakers, connected and divided by a selectively permeable membrane, and one beaker contains a salt solution, the salt solution is "hypotonic" (hypo- less, tonic - water) to the water filled beaker. One will see a migration of water into the salt solution beaker.
BOTH diffusion and osmosis rely on concentration gradients to perform their jobs. They always want "equilibrium" between both sides of the membrane.
3 - Active transport - Proteins embedded in the cell membrane move large molecules through the cell membrane or AGAINST the concentration gradient. The size one is obvious; If it's really big, it won't permeate the membrane. As for the concentration gradient, this means that it moves a molecule INTO the area with and already HIGHER concentration. If this happens with say... H+ molecules, it creates a potential difference - ie - Voltage across the membrane. Cellular respiration counts on this process to create ATP/Energy for the cell.
Wiki User
∙ 6y ago
Wiki User
∙ 6y agoThis question shows something of a misconception. Molecules have no volition so they don't 'use' any method. The process by which molecules move in and out of cells is either diffusion or active transport. I expect diffusion is the more common.
Wiki User
∙ 12y agothis is just like wikipedia where u can right your own answer gosh
Wiki User
∙ 14y agopasive transport
Wiki User
∙ 9y agomerr
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Mitosis
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What goes through the cell membrane?
Nonpolar molecules (example: lipids) Small polar molecules such as water
Why do passenger molecules need to be helped by the carrier protein?
Some molecules can't go through the cell membrane.
Which molecues cross the membrane of a cell easily and which do not?
Non-polar molecules (such as fatty acids, steroid hormones and O2) pass freely through the cell membrane. Small uncharged molecules (such as H2O) also pass freely, but are slower. Large, polar molecules and ions (such as Na+ and K+) do not pass freely. Macromolecules (such as proteins and polysaccharides) do not pass through the cell membrane. Molecules and ions that cannot pass freely through the cell membrane rely on other means, such as protein transporters, to move in to the cell.
Which substance could pass through the cell membrane readily?
Small molecules, such as water, oxygen, and carbon dioxide.
What is the meaning of selectively permable?
Selectively permeable means that only certain objects can pass through. I've encountered that phrase in cell Biology, when talking about cell membranes. The cell membrane is made of phospholipids that only allow certain substances through. Water can pass through because the molecules are small enough to pass through small holes in the membrane. Other molecules, such as sodium or potassium, can be transported using protiens.
How do small molecules get through the cell membrane against a concentration?
How do small molecules get through a cell membrane
What part of the cell membrane allows small molecules to pass through?
the cell membrane
What goes through the cell membrane?
Nonpolar molecules (example: lipids) Small polar molecules such as water
What kinds of molecules pass through a cell membrane most easily?
small and hyrdophobic molecules
What kind of molecules can easily pass through a cell membrane?
Small, Non-polar molecules. If the molecule is polar, it sticks to both sides of the membrane, and has to go through selective routes. The easiest to get through is the Non-polar (oxygen and carbon).
Why do passenger molecules need to be helped by the carrier protein?
Some molecules can't go through the cell membrane.
Molecules can pass through the cell membrane of the human cell?
The molecules that can pass through the cell membrane of the human cell include water. Other molecules include fat soluble vitamins.
When do molecules not get through the cell membrane?
when your not breathing
What is meant by cell membrane is semipermeable?
It allows only certain molecules to pass through.
Describe the water molecules move through the cell membrane during osmosis?
Describe how water molecules move through the cell membrane during osmosis?
How do you large molecules and ions pass through the cell membrane?
Recently had a homework on the cell membrane, i do know that larger molecules that cant fit through the polar heads into the cell (like gases can...and small molecules?!) can get through only if they qualify the shape fitting of the channel protein- the one that reaches all the way from the outside to the inside of the membrane. hope this helps
What type of molecules can easily go through your cell membrane or are permeable to the cell membrane?
Substances with a hydrophillic-lipophillic balance are permeable through the cell membrane.
