Transport Across The Cell Membrane Flashcards
What is the cell membrane made of?
proteins and phospholipids
What does selectively permeable mean?
Passive(Diffusion and Osmosis) and Active Transport
What does selectively permeable mean?
it only lets certain substances through the membrane
What is passive transport?
It occurs down a concentration gradient and does not require energy.
What is diffusion?
The movement of molecules from an area of high concentration to an area of low concentration.
What is osmosis?
Movement of water molecules from a higher water concentration to a lower water concentration through a selectively permeable membrane
What happens to animal cell is pure water solution?
Animal cell take in water by osmosis and swell and eventually burst
What happens to animal cell is strong salt solution?
Animal cell lose water by osmosis and shrink
What happens to plant cell in strong salt solution solution?
Plant cells lose water by osmosis and become plasmolysed
What happens to plant cell in pure water solution?
Cell gain water by osmosis and become turgid
What is active transport?
the movement of ions or molecules across a cell membrane from a region of lower concentration to a region of higher concentration, assisted by enzymes and requiring energy.
Describe differences between passive and active transport?
Passive transport is down concentration gradient while other is against
Which type of transport involves membrane proteins?
Active Transport
What denatures at high temperature and by acid?
Proteins
What dissolves in ethanol?
Phospholipids
What Substances can diffuse in out out of animal cell?
Oxygen CO2 Glucose
What do you use to test for Starch and what colours does it start and ends as?
Iodine solution it starts at brown and ends at blue/blacl
What do you use to test for Glucose and what colours does it start and ends as?
Benedict solution is starts as blue and ends as brick red.
What molecule can pass trough the cell membrane and why(starch or glucose)?
Glucose because it’s small enough to diffuse while starch cells are too big
Why do plant cell not burst when placed in water solution?
Because of the cell wall protecting it?
What advantage is to a plant if it’s turgid?
They can store water and they can help keep the cell upright
What factors affect active transport?
Glucose concentration
Oxygen concentration
Temperature
Anything that limits respiration as it provides energy for the process
