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27 Cards in this Set

  • Front
  • Back
What can move into and out of cells?
Passive Transport
How do cells maintain homeostasis?
Active Transport
What is the movement of substances across the cell membrane without the use of energy by the cell?
Passive transport
What is the movement of a substance from an area of high concentration to an area of lower concentration?
What is the diffusion of free water molecules across a selectively permeable membrane?
What are proteins that have a pore through which ions can cross the cell membrane?
Ion channels
What transports a substance across the cell membrane down the concentration gradient of the substance in facilitated diffusion?
a carrier protein
What is the movement of a substance against the concentration gradient of the substance and requires cells to use energy?
Active Transport
In animal cells, the sodium-potassium pump use energy supplied by this to transport sodium ions out ATP the cell and potassium ions into the cell.
What is the main energy currency of cells?
What is transported out of the cells by the sodium-potassium pump?
sodium ions
What is transported into the cells by the sodium-potassium pump?
Potassium Ions
During what are substances moved into a cell by a vesicle that pinches off from the cell membrane?
During what are substances inside a vesicle released from a cell as the vesicle fuses with the cell membrane?
What do communication between cells often involve?
single molecules that bind to receptor proteins on cells.
What are 3 ways a single molecule that binds to a receptor protein on a cell change the activity of the cell?
1. by enabling specific ions to cross the cell membrane
2. by causing the formation of a second messenger
3. by speeding up chemical reactions inside the cell.
hypertonic solution
water moves out of the cell
Water moves into the cell
What happens to a cell when water moves out?
It Shrinks
What happens to a cell when water moves into the cell?
the cell swells and gets larger
What is a doughnut-shaped transport protein with a polar pore through which ions can pass?
ion channel
What moves substances with the concentration gradient?
Passive transport
What moves substances against the concentration gradient?
active transport
What is a transport protein that carries a specific substance across a cell membrane?
carrier protein
What is a protein that binds to a specific signal molecule, enabling the cell to respond to the signal molecule?
receptor protein
What is a signal molecule produced in response to the binding of a chemical signal?
second messenger
What alters the chemical activity within the cell?
second messenger