Transport Across the Cell Membranes

Key Questions

• How is a concentration gradient related to the process of diffusion?

  Molecules diffuse from areas of high concentration, to areas of low concentration, down a concentration gradient.

  The concentration gradient therefore represents the concept that, just as a ball rolls down a slope, during diffusion molecules move down the concentration gradient.

  Higher concentration gradients will result in higher rates of diffusion. As the molecules move the gradient evens out until equilibrium is reached.
  

  Rogan T. · 18 · Feb 11 2015

• Question #32fee
• What is facilitated transport?
• What is the difference between passive and active transport?
• How does filtration across cell membranes occur?
• What is this process when cells use passive and active transport to move materials across the cell membrane for the maintenance of a constant internal environment within the cell?
• Will glucose be able to move across a cell membrane by simple diffusion? Why or why not?
• What is uniport, symport, antiport membrane transport?
• What are three transport processes in cells that do not require energy?
• Why is it advantageous for cells to have active transport mechanisms?
• How does a phospholipid bilayer affect the movement of substances across membranes?
• Why do molecules like glucose require a carrier protein to get across the cell membrane?
• How does oxygen and carbon dioxide move across cell membranes in humans?
• Which method(s) of cellular transport require energy? Which method(s) do not?
• Question #064b2
• What are some substances that are transported through the cell membrane by simple diffusion?
• What is the role of the cell membrane in both active and passive movement of molecules?
• What is the type of cellular transport that moves substances against the concentration gradient?
• Is energy required to move oxygen molecules across the cell membrane from an area of high concentration to an area of low concentration?
• How do molecules move across the plasma membrane?
• What is the effect of suspending the cells in hypotonic, hypertonic and isotonic environment?
• What direction will water move if a cell is placed in a hypotonic solution?
• How does the sodium-potassium pump work?
• How does the Na+/K+ pump affect the ion distribution in a neuron?
• What would happen if the sodium potassium pump was destroyed in a cell?
• How does the sodium potassium pump differ from facilitated diffusion?
• How would you explain the mechanism of sodium-potassium pump?
• What is the sodium potassium pump an example of?
• What is the purpose of the Na+ and K+ pumps in animals?
• What molecules are losing energy (known as oxidation) and gaining energy and (known as a reduction) in the electron transport chain?
• What will happen to the percentage of glycated hemoglobin if blood sugar increases?
• How do the nutrients from food get into the cell?
• How do carrier proteins work?
• What is the structure and function of "electron transport chain" in chloroplast and mitochondria?
• What molecule does oxygen become a part of at the end of the electron transport chain?
• Where in the mitochondrion does the electron transport chain take place?
• In prokaryotes, where is the respiratory electron transport chain located?
• What is the difference between oxidative phosphorylation and the electron transport chain? Are they synonymous or does one follow the other?
• How does the electron transport system work?
• Question #0e704
• What are passive and active transport?
• Why do we need sodium?
• What is one example of active transport?
• What is the sodium potassium pump? How does it work?
• What does the sodium-potassium pump use?
• What role does the sodium-potassium pump perform in the body?
• How does the sodium-potassium pump work in nerves cells?
• The sodium-potassium pump is important in what cell function?
• How would you explain active transport of Na+ and K+ in plasma membrane?
• What is the sodium-potassium pump, and what is its functional significance?
• What does a sodium potassium pump do for a cell?
• Where do you think the sodium-potassium pumps are made in the cell, and how do you think they become inserted into the lipid bilayrer of the plasma membrane?
• What is the action of the sodium-potassium pump?
• What are three functions of the Na+ K+ pump?
• The sodium potassium pump uses (what) to pump (what) out of the cell and (what) into the cell?
• The function of ATP during the operation of the sodium-potassium pump is to do what?
• Why is the sodium-potassium pump important?
• What is the sodium-potassium antiport exchange pump?
• What molecules are involved in the sodium potassium pump?
• What is the function of ATP during the operation of the sodium-potassium pump?
• How do things get in and out of cells?
• What is bulk transport?
• How is waste removed from the cell?
• What are the special structures in the cell membrane that allow materials such as water and sugar to pass through made of?
• What kinds of materials may be prevented from passing through a cell membrane?
• What do you call movement across a cell membrane that does not require energy from the cell?
• What is a portal vein?
• If a food does not turn Biuret solution violet do you know what nutrients the food contains?
• What part of the membrane do small uncharged particles diffuse through?
• Question #fc7ff
• How do substances move in passive transport?
• How does potassium ions enter a cell?
• Why do materials diffuse across a membrane?
• What two processes allow materials into and out of cells?
• Why are transport proteins needed in the cell membrane?
• Question #32ac4
• Question #924dc
• What sort of molecules could easily cross the non-polar region occupied by the tails of the two layers of a phospholipid?
• If phospholipids were placed in a non-polar solution, would they still form a bilayer?
• What will happen if a bacterial cell is placed in a hypotonic solution with penicillin?
• Question #4a30d
• What is cellular transport?