Chap+3+JO

(1) p. 31 Describe the structure of a phospholipid (insert an image). Indicate the parts that hydrophillic and the parts that are hydrophobic. The structure is that of a polar head and two nonpolar tails. The tails are hydrophobic while the heads face towards the liquid and are hydrophilic.

(2) p. 31 How do phospholipids arrange themselves in water? The heads face towards the water while the tails create an interior. ( the tails on both sides face each other)

(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? The fluid mosaic model is a working description of membrane structure and states that the protein molecules form a shifting pattern within the fluid phospholipids’ bilayer. The outer surface consists of the phospholipids’ heads and proteins. The inner surface consists of the tails.

(4) p. 46 What is the function of the membrane? How does the structure of the membrane suit that structure? The membrane keeps everything intact. It only allows certain things to enter and/ or leave the cell.

(5) p. 46 Why is the membrane considered selectively permeable? It is selective because it chooses what goes, what stays and what comes.

(6) p. 46 What is diffusion? Give an example. Diffusion is the random movement of molecules from the area of high concentration to lower concentration until equal. An example would be that of the smell of a cookie within a house, the example is located in the book. But in short the smell starts in one room and as a door is opened the smell defuses and spreads to fill the other room. This process continues until all rooms are filled.

(7) p. 46 What is osmosis? Osmosis is the diffusion of water across a permeable membrane.

(8) p.46 How do isotonic, hyptonic, and hypertonic solutions differ and how does each affect cells? (insert an image) Isotonic solution is when the cells remain the same. Hypotonic is when the cells gain water and are about to burst. Hypertonic is when the cells lose water and shrink.

(9) pp. 46-47 What is the difference between passive and active transport? During active transport a molecule is moving contrary to the normal direction, that is, from lower to higher concentration.

(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 is random movement, Facilitated is rushed, Active is moving contrary to the norm, endo they are taken in exo they are removed. The active ways are active, diffusion and endo. Passive would be felicitated and exo.

(11) p. 47 What is the difference between exocytosis and phagocytosis? Phagocytosis is a process for endocytosis and it helps removes pathogens. Exocytosis the vesicles fuse with the membrane.

(13) pp. 54-55 Which molecule captures the energy released from glucose? How many molecules are produced per glucose? The molecule is Glycolsis, it captures and splits glucose/ sugars.

(14) p. 55 What is the role of oxygen in cellular respiration? The role of oxygen is the final acceptor of electrons at the end of the chain.

(15) p. 55 Where does carbon dioxide come from in cellular respiration? It comes in during the citric acid cycle.

(16) p. 56 What is fermentation? How many ATP are produced per glucose molecule? Fermintation is an anerobic process by which no oxygen is needed. Only 2 ATP per glucose molecule.