Passive Transport
Does passive transport require energy ATP?
No!
Does active transport require energy?
Yes
Which type of transport requires ATP?
Active
Define osmosis.
The diffusion of water
What is the main goal of all types of cell transport?
To maintain homeostasis
Molecules move from ______ to ______ concentration in passive transport.
High to low
In active transport, substances move from ______ to ______ concentration.
Low to high
Which type of transport moves substances with the concentration gradient?
Passive
A cell is placed in pure water and swells — what type of solution is this?
Hypotonic
What process brings large materials into the cell?
Endocytosis
What is the diffusion of water?
Osmosis
What is the main reason cells use active transport instead of passive transport?
Because they need to move substances against their concentration gradient (from low to high). Something passive transport cannot do.
A cell uses energy to pull in amino acids from a low concentration outside to a higher concentration inside.
Active
A cell is placed in salt water and shrinks — what type of solution is this?
Hypertonic
Why is the cell membrane often called “selectively permeable”?
Because it controls what enters and leaves the cell, allowing some substances to pass while blocking others.
If the concentration of oxygen is higher outside a cell than inside, which direction will oxygen move?
It will move into the cell by diffusion, because passive transport moves substances from high to low concentration.
A white blood cell surrounds and EATS a bacterium.
What type of active transport is this an example of?
Endocytosis (phagocytosis)
Oxygen moves across the membrane. Is this passive or active transport?
Passive
A cell is placed in a solution with equal solute concentration — what type of solution is this?
Isotonic
When you put salt on a slug, it shrivels up and dies.
What process is responsible for this, and what happens to the water in the slug’s cells?
Osmosis; water leaves the slug’s cells because the salty environment is hypertonic, causing the cells to lose water and shrink
Give an example of a molecule that moves by facilitated diffusion
Glucose or ions
A cell takes IN nutrients by forming small vesicles around the liquid.
What is this process called?
Endocytosis (pinocytosis)
Compare the role of proteins in passive vs. active transport.
Passive = channel proteins (no energy)
Active = carrier proteins + ATP
More solute outside of the cell
Hypertonic
Why do cells need mitochondria in order for active transport to occur efficiently?
Mitochondria produce ATP, which provides the energy required for active transport