Transport across a cell membrane Flashcards
What is actve transport?
the movement of molecules and ions across a cell membrane against a concentration gradient. It requires energy and they are moved by carrier protiens. The energy is provided by ATP
What substances can travel using active transport
Glucose and iodine
What would happen to a leaf cell when placed in a concentrated sugar or salt solution
The water would leave the cell and become smaller
What would happen to a red blood cell when in a water solution?
Water would go into the cell and burst it
What is osmosis?
Movement of water molecules from a region of high to low water concentration
What happens to a cell when placed in a isotonic solution
No change
Why can glucose move across the cell membrane but not starch
Glucose is smaller in size then starchy; starch is too big to pass through
Name 4 substances that can move by diffusion
Oxygen, Carbon Dioxide, Glucose and urea
What is diffusion?
Diffusion is he movement of molecules or ions from a region of high to low concentration
What is diffusion used for?
Diffusion allows substances to move within a cell from one area to another as well as allowing material to enter and leave a cell. Diffusion continues until the concentration of substance is even throughout
What is the function of the cell membrane
The function of the cell membrane is to control which substances enter and leave the cell- they are said to be selectively permeable
What are substances that can pass through the membrane?
Fatty acid, Amino Acid, Glucose, Oxygen, Carbon Dioxide
What are substances that can’t pass through the membrane
Starch, proteins, and fats
What is the cell membrane made off?
Lipids (liquid fat) and proteins
