Unit 4: Cellular Processes - Passive & Active Transport Flashcards
What is cell transport?
The movement of substances across the cell membrane
What is the concentration gradient?
The difference in concentration of a substance across a space or membrane.
How does passive transport move?
Down, or with the gradient (HIGH TO LOW)
Is energy used in passive transport?
No.
How does active transport move?
Up, or against the gradient (LOW TO HIGH)
Does active transport use energy?
Yes.
What are the different types of passive transport?
Diffusion, facilitated diffusion, osmosis
What happens during diffusion?
Molecules move down (WITH) the concentration gradient, from high to low.
What sizes are the molecules during diffusion?
Small, non-polar
What type of passive transport moves directly across the cell membrane?
Diffusion
What happens during facilitated diffusion?
Protein channel allows polar and large molecules to diffuse across
What is an aquaporin?
A protein channel for water
What type of passive transport is aquaporin?
Facilitated diffusion
What is osmosis?
The diffusion of WATER across membrnae
How does osmosis work?
Aquaporins, but water can also do regular diffusion
Which way does osmosis move?
High water concentration (low solute) to low water (high solute)
What are the main types of active transport?
Primary, secondary, endocytosis, and exocytosis.
What is active transport?
Molecules move against the concentration gradient by using energy.
What happens to ATP in active transport?
ATP is converted to ADP once it is used.
What does ATP stand for?
Adenosine triphosphate
What does ADP stand for?
Adenosine Diphosphate
What does primary diffusion do?
It directly uses energy through a protein channel
What is secondary diffusion?
Uses the energy generated from the concentration gradient of one molecule to drive the transport of another molecule against its gradient.
What are the 2 types of secondary diffusion?
Symport and antiport
What is symport?
Both molecules move in the same direction across the membrane
What is antiport?
Molecules move in opposite directions across the cell membrane
What types of molecules use endocytosis and exocytosis?
Molecules that are too big for both diffusion and protein channels
What is endocytosis?
Engulfing substances into the cell by forming vesicles (pieces of membrane)
What is exocytosis?
Expelling substances out of the cell via vesicles.
What are the three types of tonicity?
Isotonic, hypotonic, and hypertonic
What is an isotonic solution?
Solute concentration of a cell and its environment are essentially equal.
What is a hypotonic solution?
Water enters into the cell, and the cell will grow and eventually lyse.
Where is the most solute in a hypotonic solution?
Less solute outside the cell, more inside.
What is a hypertonic solution?
More solute (LESS WATER) outside of the cell, water is drawn out of the cell (loses water), and cell shrivels
Where is the most solute in a hypertonic solution?
More solute is outside of the cell, so less inside.
If outside the cell is hypertonic, what is the inside of the cell?
Hypotonic
If the inside of the cell is hypotonic, what solution is it?
hypertonic
Is tonicity active or passive transport?
Passive
