1. Homeostasis and Cell Transport
Vocabulary Review
Homeostasis and
Cell Transport

2. The movement of substances across a cell membrane without any input of energy
Passive Transport

3. The movement of molecules from an area of higher concentration to an area of lower concentration
Diffusion

4. The difference in the concentration of molecules across a distance
Concentration gradient

5. Concentration of molecules is the same throughout the space the molecules occupy
Equilibrium

6. Movement of water molecules from high concentration to low concentration
Osmosis

7. Concentration of solute molecules outside the cell is LOWER than in the cytosol; water diffuses into the cell
Hypotonic

8. Concentration of solute molecules outside the cell is HIGHER than in the cytosol; water diffuses out of the cell
Hypertonic

9. Concentrations of solutes outside and inside the cell are equal
Isotonic

10. Organelles that remove water through contraction
Contractile Vacuoles

11. The pressure that water molecules exert against the cell wall
Turgor pressure

12. The shrinking of a cell due to water’s moving out the cell when placed in a hypertonic environment
Plasmolysis

13. The swelling and eventual bursting of a cell as water moves into it when placed in a hypotonic environment
Cytolysis

14. Facilitated Diffusion
The movement of substances across a cell membrane with the assistance of protein carriers
Facilitated Diffusion

15. The proteins that move certain molecules into the cell that cannot readily diffuse through the cell membrane
Carrier Proteins

16. A complex of protein molecules in a cell membrane that form a pore through which ions can pass
Ion Channels

17. The movement of chemical substances, usually across the cell membrane, against a concentration gradient; requires energy
Active Transport

18. Sodium-Potassium Pump
A carrier protein that uses ATP to actively transport sodium ions out of a cell and potassium ions into the cell
Sodium-Potassium Pump

19. The process by which a cell membrane surrounds a particle and encloses the particle in a vesicle to bring the particle into the cell
Endocytosis

20. Small cavity or sac that contains materials; forms when part of the membrane surrounds the materials to be taken into or out of the cell
Vesicle

21. A method of active transport across the cell membrane in which the cell takes in extracellular fluids
Pinocytosis

22. The process by which a cell engulfs large particles or whole cells, either as a defense mechanism or as a means to obtain food
Phagocytosis

23. A cell that ingests and destroys (digests) foreign matter or microorganisms
Phagocyte

24. The process by which a substance is released from the cell through a vesicle that transports the substance to the cell surface and then fuses with the membrane to let the substance out
Exocytosis