Drew's+p31+hw

(1) p. 31 Describe the structure of a phospholipid (insert an image). Indicate the parts that hydrophillic and the parts that are hydrophobic. They have a phosphate group. They are constructed like fats, except in place of the third fatty acid, there is a phosphate group that contains phosphate and nitrogen

(2) p. 31 How do phospholipids arrange themselves in water? They face outward towards watery solutions.

(3) p. 46 Describe the fluid-mosaic model of a membrane. (insert an image) Which components are the fluid, and why? Which components are the mosaic, and why? Says that protein molecules form a shifting pattern within the fluid phospholipid bilayer.

(4) p. 46 What is the function of the membrane? How does the structure of the membrane suit that structure? It marks the boundry between the outside and the inside of the cell.It is positioned to face toward the watery environment.

(5) p. 46 Why is the membrane considered selectively permeable? Small molecules can pass through the membrane easily

(6) p. 46 What is diffusion? Give an example. Random movement of molecules from a higher concentration to a lower concentration.

(7) p. 46 What is osmosis? Diffusion of water across a plasma membrane.

(8) p.46 How do isotonic, hyptonic, and hypertonic solutions differ and how does each affect cells? (insert an image) The tonicity is the concentration of the solute in a solution.

(9) pp. 46-47 What is the difference between passive and active transport? Active transport is a molecule moving contrary to the normal direction.

(10) pp. 46-47 What are the various ways substances can enter and exit cells? (diffusion, facilitated transport, active transport, endocytosis, exocytosis) Which are passive and which are active ways of crossing the cell?

(11) p. 47 What is the difference between exocytosis and phagocytosis? Exocytosis is when a vesicle fuses with the plasma membrane as secretion occurs. Phagocytosis is is when cells take up molecule and fluid.

(12) p. 54 What is the overall formula of cellular respiration? What are the reactants and what are the products? It breaks down glucose to carbon dioxide and water

(13) pp. 54-55 Which molecule captures the energy released from glucose? How many molecules are produced per glucose? Glycosis

(14) p. 55 What is the role of oxygen in cellular respiration? The presence of oxygen makes the citric acid cycle and the electron transport chain aerobic.

(15) p. 55 Where does carbon dioxide come from in cellular respiration? It comes from glucose.

(16) p. 56 What is fermentation? How many ATP are produced per glucose molecule? Fermentation is when oxygen is not available to the cells and the electron transport chain becomes inoperative because the oxygen is not present to accept electrons.

(17) p.56 What is the waste product of yeast fermentation? It produces alcohol and CO2.