Related Essays

  • Functions, Role, And Structure Of A Cell Membrane

    Active transport is when ions or molecules move against a concentration gradient going from a region of lower concentration to higher concentration. Carbohyd...

  • Osmosis Research Paper

    With transports there are two types, passive and active. Passive transport moves molecules and other substances across the membrane, but unlike active transp...

  • Cell Transport Lab Report

    Active transport however, requires the use of ATP, or energy, to move across the membrane. Diffusion is the movement of

  • Cell Theory Research Paper

    Mechanisms of active transports include ATP- dependent pumps creating energy from ATP in order to carry solutes and light-driven pumps use the energy from th...

  • Active Transport Essay

    The Effect of Active Transport on the Movement of Glucose Against the Concentration Gradient within the Small Intestine of a Rat Introduction The movement ...

  • First And Second Laws Of Thermodynamics

    Active transport is when a cell uses a transport protein to move a substance against its concentration gradient from where it is less concentrated to where i...

  • Nonpolar Parts Of A Phospholipid Essay

    Facilitated diffusion 13. In this transport process, the energy from hydrolysis of ATP is used to drive substances across the membrane against their o...

  • Facilitated Diffusion

    An example of facilitated diffusion can be seen in the movement of glucose across the plasma membrane of red blood cells in order to be used as energy. The r...

  • Facilitated Diffusion Research Paper

    • Large molecules such as sugar diffuse across the plasma membrane by the help of a carrier protein in a process known as ‘Facilitated Diffusion’. • If the...

  • Homeostasis: Cell Membrane Proteins

    Symport, the carrier transports two substances in the same direction...into or out of the cell...antiport, one substance moves into the cell and the other mo...

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

Card Range To Study

through

image

Play button

image

Play button

image

Progress

1/6

Click to flip

Use LEFT and RIGHT arrow keys to navigate between flashcards;

Use UP and DOWN arrow keys to flip the card;

H to show hint;

A reads text to speech;

6 Cards in this Set

  • Front
  • Back
Active transport

The movement of molecules or ions into or out of a cell from a region of lower concentration to a region of higher concentration using ATP and carrier proteins.
ATP and active transport

ATP is used to:


- directly move molecules


individually move molecules using a concentration gradient.


- individually move molecules using a concentration gradient which has already been set up by active transport (co-transport).
Active transport differs from passive forms of transport, why?

1) Metabolic energy in the form of ATP is needed.


2) Substances are moved against a concentration gradient, low to high.


3) Carrier protein molecules act as 'pumps'.


4) The process is very selective, with specific substances being transported.

How active transport works


1) The carrier protein span the plasma membrane and bind to the molecule or ion to be transported on one side.


2) The molecule or ion binds to receptor sites on the carrier protein.


3) On the inside of the cell, ATP binds to the protein causing it to split into ADP and a phosphate molecule. Due to this the protein molecule changes shape and opens to the opposite side of the membrane.


4) The molecule or ion is then released to the other side of the membrane.


5) The phosphate molecules is released from the protein which causes the protein to revert to its original shape, ready for the process to be repeated. The phosphate molecule recombines with the ADP to form ATP during respiration.


Sodium-potassium pump


Sometimes more than one molecule or ion may be moved in the same direction t the same time by active transport. Occasionally, the molecules or ions are moved into a cell/organelle at the same time.


Here, the sodium ions are actively removed from the cell/organelle while potassium ions are actively taken in from the surroundings. This process is important to an number of processes, including the secretion of the nerve impulse.