| Homeostasis & Transport Review |
1. A type of transport in which water moves across and down its concentration gradient is called ______________________________________.
2. Net movement of water across a cell membrane occurs from a ___________________ solution to a ________________________ solution.
3. A _____________________ ___________________ only allows certain molecules to pass thorough.
4. A __________________________ _____________________ is the concentration difference across space.
5. A structure that can move excess water out of a unicellular organism is a __________________________ ______________________.
6. The movement of some substances, without any input of energy by the cell, is called ________________________ ________________________.
7. The process of diffusion requires________________________________________________
___________________________________________________________________________.
8. If the molecular concentration of a substance is the same throughout space, the substance is in ____________________________________.
9. All forms of passive transport depend on the ___________________ ________________ of molecules.
10. The movement of molecules from an area of higher concentration to an area of lower concentration is called ______________________________.
11. Sodium-potassium pumps move ___________________ ions _______________ of the cell and ___________________________ ions ___________________ the cell. This causes the inside of the cell to have what type of charge? __________________________.
12. Most of the time, the environment that plant cells live in is ________________________.
13. Plasmolysis of a human red blood cell would occur if the cell were in a(n) ____________________________ ____________________________.
14. The bursting of cells is called _____________________________.
15. The pressure that water molecules exert against a cell wall is called ___________________ _________________________________.
16. A membrane bound organelle used in endocytosis is called a _______________________.
17. A relatively high solute concentration is called _____________________________.
18. The uptake of large particles is called ________________________________.
19. The shrinking of cells is called _____________________________________.
20. A relatively low solute concentration is called ___________________________.
21. The uptake of solutes or fluids is called ________________________________.
22. Molecules always diffuse ___________________ their concentration gradient.
23. The diffusion of water across a membrane is called __________________________.
24. In an ________________________ _____________________ the concentration of solutes outside and inside the cell are equal.
25. Transport that requires the cell to expend energy is called _____________________ ________________________________.
26. Which type of molecule forms a bilayer within a cell membrane? __________________________________
27. Most food and wastes materials that move into and out of a cell go through ____________________________ ________________________________.
28. Glucose molecules cross the cell membrane by means of ______________________________ _______________________________.
29. Ridding the cell of material by discharging it from sacs (vesicles) at the cell surface is called ____________________________________________________.
30. Molecules that are too large to be moved across a cell membrane can be removed from the cell by ________________________________________________.
31. A substance that dissolves in another substance is called a (n) _________________________________________.
32. The diffusion of ___________________________ through the cell membranes is called osmosis.
33. When water enters the cell, it creates pressure. This pressure is called _____________________________ _______________________________________________.
34. A cell does not expend __________________________ when diffusion takes place.
35. __________________________ is the most common solvent in cells.
36. A cell membrane is said to be _______________________________________ permeable because it allows the passage of some solutes and not others.
37. Facilitated diffusion and active transport are two types of ________________________________ transport.
38. __________________________ _______________________________ allows a cell to stockpile substances in far greater concentrations that they occur outside the cell.
39. Active transport systems are a form of cell transport that requires energy from molecules of __________________________________________________.
40. The process in which an amoeba engulfs its prey and takes it in is known as _______________________________________________________________.
For each of the following, Identify the transport type:
a) A cell membrane encloses and takes in a droplet of fluid.______________________________
b) Carrier proteins use energy and act as a pump to move nutrients into a root cell. ____________________________________________
c) Carrier proteins take sugar (glucose) into a cell without requiring energy input. ____________________________________________
d) Water diffuses across a cell membrane from a region of high concentration to a region of low concentration. _______________________________________
e) Mucus and waste products packaged by Golgi apparatus are secreted by a cell. ________________________________________
f) A cell membrane encloses and takes in food particles. ________________________________
DIRECTIONS: Read Chapter 5, Homeostasis and Transport, and Answer the questions below as completely and as thoroughly as possible. Answer the question in essay form (not outline form), using complete sentences. You may use diagrams to supplement your answers, but a diagram alone without appropriate discussion is inadequate.
1. Name and Describe Three types of passive transport AND Three types of active transport.
2. How do ions cross the lipid bilayer of the cell membrane?
3. Toward what condition does diffusion eventually lead, in the absence of other influences?
4. Explain the difference between pinocytosis and phagocytosis.
5. What is the fundamental difference between carrier proteins that participate in facilitated diffusion and carrier proteins that function as pumps.
6. Explain the difference between passive transport and active transport.
7. Describe what would happen to the molecules in a drop of ink dropped into a beaker of water. What is this process called?
8. What would happen to a freshwater unicellular organism if its contractile vacuole stopped functioning? Explain your answer.
9. How is osmosis related to diffusion?
10. Contrast endocytosis with exocytosis.
11. Define a hypotonic, hypertonic and isotonic solution.
12. Describe the action of the sodium-potassium pump.
13. Three red blood cells are placed in hypertonic, hypotonic, and isotonic solutions. Compare the behavior of the three cells. Explain your answer on the basis of concentration gradients, diffusion, and give the name of the effects.
All these water molecules attracting each other mean they tend to clump together. This is why water drops are, in fact, drops! If it wasn’t for some of Earth’s forces, such as gravity, a drop of water would be ball shaped — a perfect sphere. Even if it doesn’t form a perfect sphere on Earth, we should be happy water is sticky. Water is called the “universal solvent” because it dissolves more substances than any other liquid. This means that wherever water goes, either through the ground or through our bodies, it takes along valuable chemicals, minerals, and nutrients.