Transport Across Cell Membranes Flashcards
What controls what enters and leaves the cell?
The cell membrane controls what enters and exits the cell.
What does the cell membrane consist of?
The cell membrane consists of a bio-layer of phospholipids and embedded proteins.
What does a fluid mosaic model refer to?
It refers to the movement of molecules and the variety of dispersed protein.
What does ‘selectively permeable’ mean?
Selectively permeable means that the cell membrane is selective about what it lets pass through.
Name 3 permeable molecules.
Water (H2O), CO2 and non-charged molecules.
Glucose, amino acids, charges molecules and ions are an example of?
Molecules that require energy.
State 2 non-permeable molecules.
Charged and large molecules.
Describe diffusion.
Diffusion is the movement of molecules from a high concentration to a region of low concentration.
Does passive transport require energy? Why?
No, because it follows the concentration gradient.
Name 3 substances that enter the cell
Oxygen, glucose and water
Name 3 substances the leave the cell?
Carbon Dioxide and water.
Gave an example of diffusion.
Gas Exchange in animals.
What is osmosis?
Osmosis is the diffusion of water.
What is the sugar concentration of an average cell?
1% is the average sugar concentration in a cell.
What is a hypertonic solution?
A hypertonic solution had a higher concentration of sugar/salt that the cell.
What happens to an animal cell if it is placed in a hypertonic solution?
Water leaves the cell, the cell shrinks.
What happens to a plant call if it is placed in a hypertonic solution?
The cell becomes plasmolysed as water leaves the cell.
What is a hypotonic solution?
A hypotonic solution has a lower concentration of sugar/salt than the cell.
What happens to an animal cell in a hypotonic solution?
When an animal cell is in a hypotonic solution, water enters the cell causing it to burst.
What happens to a plant cell in a hypotonic solution?
When a plant cell is in a hypotonic solution the cell becomes targid as water enters the cell.
What is an isotonic solution?
An isotonic solution had no effect of the cells. The concentration is equal.
Does active transport require energy? Why?
Yes, because it moves against the concentration gradient.
What does ATP provide energy for?
ATP provides energy for active transport.
What does ATP cause?
ATP causes a change in the protein which moves non-permeable products across the cell membrane.
