membrane+structure+and+respiration

1) p. 31 Describe the structure of a phospholipid //(insert an image)//. Indicate the parts that hydrophillic and the parts that are hydrophobic. Essentially they are constructed like fats except in place of the third fatty acid there is a phosphate group or a grouping that contains both phosphate and nirogen. the head is polar and the tails are non polar. the heads form hydrophilic heads that face outward toward watery solutions and the tails from the hydrophobic interior. (2) p. 31 How do phospholipids arrange themselves in water? the heads face outward toward the water and the tails form the hydrophobic interior (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? A working description of membrane structure says that the protein molecules form a shifting pattern within the fluid phospholipid bilayer cholesterol lends support to the membrane. The membrane is composed of a phospholipid bilayer in which proteins are embedded the hydrophilic heads of phospholipids are a part of the oustide surface and the inside surface of the membrane. The hydrophobic tails make up the interior of the membrane. carbohydrate chains are attached to the outside surface and cytoskeleton filaments are attached to the inside surface.

(4) p. 46 What is the function of the membrane? How does the structure of the membrane suit that structure? The plasma membrane keeps a cell intact. Small molecules that are lipid-soluble such as oxygen and carbon dioxide can pass through the membrane easily. Water molecules can freely cross the membrane by utilizying aquaporins Ions and large molecules cant do this (5) p. 46 Why is the membrane considered selectively permeable? it only allows certain molecueles and ions to enter and exit the cytoplasm (6) p. 46 What is diffusion? Give an example. diffusion is the random movement of molecules from the area of higher concentration to the area of lower concentraition until they are equally distributed. when you mix food dye and water (7) p. 46 What is osmosis? Osmosis is the 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)// Solutions that cause cells to sell or even burst due to an intake of water are said to be hypotoic. solutions that cause cells to shirnkk due to a loss of water are hypertonic. normal body fuilds are isotonic to cells and do not effect the cells and they keep their usual shape. (9) pp. 46-47 What is the difference between passive and active transport? Passive transport is when cells move across membranes and is dependent on the permiability of the cell the four main types are diffusion, facilitated diffusion, filtration and osmosis. Active transport is when cells move across the membrane using chemical energy (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? diffusion - the ranom movement of moluecules from an area of higher concentration to an equal distribution - passive facilitated transport many solutes do not simply diffuse rather they are transported by means of protein carriers within the membrane - passive active transport a molecule is moving contrary to the normal direction that is from lower to higher concentration - active transport. Endocytosis - when a cell membrane forms a poch to envelop a substance and fluid. Excoytosis the plasma membrane secretes while a vesicle fuses (11) p. 47 What is the difference between exocytosis and phagocytosis? phagocytosis - White blood cells are able to take up oathgens by endocytosis exocytosis a vesicle fusese with the plasma membrane as secretion occurs (12) p. 54 What is the overall formula of cellular respiration? What are the reactants and what are the products? 1 2 3 4 5 6 A - B - C - D - E - F - G A represents the beginning reactant(s) and G represents the end product(s) (13) pp. 54-55 Which molecule captures the energy released from glucose? How many molecules are produced per glucose? glycosis 2 molecules per glucose (14) p. 55 What is the role of oxygen in cellular respiration? Pyruvate is a pivotal molecule in cellular respiration when oxygen is available, the molecule enters mitochondria and is broken down completely. Oxygen serves as the final acceptor of the electrons at the end of the chain. After oxygen recieves the electrons it comines with hydrogens and beomes water. (15) p. 55 Where does carbon dioxide come from in cellular respiration?

(16) p. 56 What is fermentation? How many ATP are produced per glucose molecule? an anaerobic process meaning that it does not require oxygen 2 ATP per glucose molecule (17) p.56 What is the waste product of yeast fermentation? lactate