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How would sugar entering a cell that already contains a high concentration of sugar get through a cell membrane and into the cell?
Glucose (sugar) enters the cell through facilitated diffusion, which is the movement of particles from an area of high concentration to an area with low concentration through a protein channel. This happens passively (on its own, with no extra energy required).
It does not matter what other particles are in the cell--- the GLUCOSE will enter it so long as there is a higher concentration of GLUCOSE outside the cell than inside.
The protein channel is needed because glucose molecules are too large to pass through the cell membrane by simple diffusion.
What else can I help you with?
Do you think that a plant cell which already has a stiff strong cell wall still really needs a cell membrane Why or why not?
Yes, the cell membrane is still necessary in a plant cell with a cell wall because it regulates the movement of substances in and out of the cell, controls cell communication, and plays a role in cell recognition and signaling processes. The cell membrane also helps maintain the structural integrity of the cell.
If cells are placed in a isotonic solution containing a solute to which the membrane is impermeable what could happen?
If the solution is hypotonic, that means that the concentration is less than that in the cell. Interestingly, despite the impermeability of the solute, the water still rushes into the cell to try and correct the imbalance, which causes the cell to swell and eventually burst.
What occurs when molecules ATP to pump molecules from one side of a membrane to the other?
ATP molecules release their third phosphate group in the reaction ATP --> ADP + P + Energy. The energy stored between the second and third phosphate groups is released and used by the cell to do work, such as pumping molecules across the cell membrane.
Do molecules need energy to get in and out of the cell?
To clarify the question: the molecules do not need energy to enter or exit the cell, the cells need to spend the energy to get some molecules in or out--however, the answer to your question is: It depends on the molecule, and the cell.Molecules can move into and out of cells by two broad methods: Passive transport, and Active transport.Passive transport requires no energy and involves diffusion (the moving of the molecule from an area of high concentration to low concentration WITH its concentration gradient--it spreads out, into the areas where there isn't any already). One type of diffusion is regular diffusion for molecules that can pass through the membrane (these molecules are said to be "lipophilic" as they interact with the lipid membrane easily). Another type of diffusion is facilitated diffusion--the molecule uses an open channel in the cell to move (does not pass through the membrane by itself). However, the channel is open and does not require energy to function.Active transport requires energy to work. These can be gated channels, "pumps" and other types of transport proteins. Active transport usually moves molecules AGAINST their concentration gradient (from low concentration to high concentration). This is the opposite of diffusion. Remember, the cell is paying this energy debt, not the molecule.In general, lipophilic (hydrophobic) molecules usually do not need energy to cross the cell membrane while lipophobic (hydrophilic) molecules do. The lipophobic molecules often carry a charge (positive or negative) which renders them unable to pass through the membrane, though just a partial charge (polarity) can be enough to keep them in our out. In contrast the lipophilic molecules are electronically neutral and not polar.
Does water move when a cell is in an isotonic environment?
In such a situation there is no net flow of water towards inside or outside of the cell.The flow of water is only possible in case of the placement of the cell in a hypotonic or hypertonic solutions.
How would sugar entering a cell that already contains a high concentration of sugar get through a cell membrane into a cell?
It would be Active Transport.
How do small molecules pass through the cell membrane?
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.
Why you use skim milk to block the membrane in western blotting?
The membrane binds proteins unspecifically (it will bind any).Western blotting uses antibodies to probe the proteins bound to the membrane for the one you are testing for. The antibodies bind specifically to a particular protein that you have chosen and contain a label to allow identification of them on the membrane. In this way you can see whether or not the membrane, and therefore the tissue you are testing, contains a particular protein.Antibodies are proteins. This means the antibody would bind anywhere on the membrane, as well as on the protein you're looking for, rendering the results worthless (it will ALWAYS show positive). To stop the antibodies binding to the membrane, so that they only bind to the protein (if it exists) the membrane must be blocked (completely filled with protein) so that there is nowhere on the membrane for the antibody to bind.Since milk contains a generic mix of a relatively high concentration of known proteins, it is used to block the parts of the membrane that don't already have protein on so that the antibodies won't bind there. As it is very cheap and readily available, it is a good source of protein to use. It is unlikely that a Western blot would be needed for any protein that is contained in milk, but if that is the case an alternative mixture can be used.
What did the Germans first call the concentration camps?
The term concentration camp (Konzentrationslager) was used already in March 1933.
Does osmosis occur in an isotonic solution?
In an isotonic solution, there is no net movement of water across the cell membrane, as the concentration of solutes inside and outside the cell is equal. Therefore, osmosis does not occur in an isotonic solution.
Why doesn't yanmar sell tractors in the us?
To do so, they'd be entering a market which is already dominated by competitors, and they'd be entering this market with proprietary designs. It's just not feasible for them to do this.
What is the effect of increasing the concentration of enzymes in a reaction?
If the reaction speed has not already peaked, then it will increase
What happened to magot frank after they got caught in the seret annex?
she was already in concentration camp
Do you think that a plant cell which already has a stiff strong cell wall still really needs a cell membrane Why or why not?
Yes, the cell membrane is still necessary in a plant cell with a cell wall because it regulates the movement of substances in and out of the cell, controls cell communication, and plays a role in cell recognition and signaling processes. The cell membrane also helps maintain the structural integrity of the cell.
If cells are placed in a isotonic solution containing a solute to which the membrane is impermeable what could happen?
If the solution is hypotonic, that means that the concentration is less than that in the cell. Interestingly, despite the impermeability of the solute, the water still rushes into the cell to try and correct the imbalance, which causes the cell to swell and eventually burst.
Who must yield at a roundabout?
A driver must always look to the left and yield to a vehicle that is already in the roundabout.
What happens when you mix 20 volume creme developer with colorsilk that has developer already?
Mixing a 20 volume creme developer with a dye that already contains developer may result in an overly strong developer concentration, which can be damaging to your hair. It's generally recommended to use developer specific to the dye you're using to ensure proper color development and hair health.
