Membrane+Structure+and+Respiration+WG

(1)p. 31 Describe the structure of a phospholipid (insert an image). Indicate the parts that hydrophillic and the parts that are hydrophobic. The phospholipids are structured like fats, but one fatty acid is replaces by a polar phosphate group. The hydrophilic heads face outwards toward watery solutions and the tails form the hydrophobic interior. (2) p. 31 How do phospholipids arrange themselves in water? They are arranged outward, and they also spontaneously form a bilayer. The tails also form the hydrophobic interior.

(3) p. 46 Describe the fluid-mosaic model of a membrane. It is a working description of membrane structure; The model says that the protein molecules form a shifting pattern within the fluid phospho-lipid bilayer. Which components are the fluid, and why? Which components are the mosaic, and why? The glycoprotein’s and glycolipids are mosaic and the reason why is because they have carbohydrate chains.

(4) p. 46 What is the function of the membrane? The membrane keeps a cell intact. It allows only certain molecules and ions to enter and exit the cytoplasm freely.

(5) p. 46 Why is the membrane considered selectively permeable? Because small molecules that are lipid-soluble, such as oxygen and carbon dioxide, can pass through the membrane easily.

(6) p. 46 What is diffusion? Diffusion is the random movement of molecules from the area of higher concentration to the area of lower concentratio, until they are equally distributed. Give an example. An example is a person remembering the aroma of something.

(7) p. 46 What is osmosis? Osmosis is the diffusion of water across plasma membrane. It involves water and a solute that cannot readily cross the plasma membrane.

(8) p.46 How do isotonic, hyptonic, and hypertonic solutions differ and how does each affect cells? Hypotonic: hypotonics are solutions that cause cells to swell or even burst due to an intake of water. Water enters the cells and they sell to bursting. Isotonic: intravenous solutions medically administered. It maintains the cells size and shape Hypertonic: hypertonics are solutions that cause cells to shrink or shrivel due to loss of water. When water leaves cells osmosis pressure occurs.

(9) pp. 46-47 What is the difference between passive and active transport? Active transport is a molecule when a molecules move contrary to the normal direction, and forms lower the higher concentration. Passive transport is very different because there is a (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 and facilitated transport are passive and the rest are active ways of crossing the cell.

(11) p. 47 What is the difference between exocytosis and phagocytosis? During exocytosis, a portion of the plasma membrane invaginates, or forms a pouch to envelop a substance and fluid. During exocytosis, a vesicle fuses 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? Reactants are the thing that are reacting from A to G. no reaction in the pathway occurs unless its enzyme is present.

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

(14) p. 55 What is the role of oxygen in cellular respiration? The oxygen has no role in cellular reparation. Its role is not required.

(15) p. 55 Where does carbon dioxide come from in cellular respiration? In cellular repiration, corbon dioxide comes from the citric acid cycle.

(16) p. 56 What is fermentation? Fermentation is an anaerobic process, in other words it doesn’t require oxygen. When the oxygen is not available in the cells, the electron transport chain soon becomes inoperative because oxygen is not present to accept electrons. How many ATP are produced per glucose molecule? Only two ATP are produced per glucose molecule.

(17) p.56 What is the waste product of yeast fermentation? The waste product for yeast fermentation is carbon dioxide, instead of Lactate.