- If a mutation in a sodium channel in an Intestinal epithelial cell caused a marked decrease in the concentration gradient of sodium across the plasma membrane, which of the following would you expect to observe?
- the beaker contains two solution solutions of salt (A: .2M salt) (B: .9M salt). They are separated by a membrane that is permeable to both salt and water. There will be what movement of salt and water?
- Which mechanism best describes the process by which nutrients are taken up selectively at the apical surface of the epithelial cells that line the gut and released from their basal and lateral surfaces?
- Below are listed molecules with different chemical characteristics. Knowing that all molecules will eventually diffuse across a phospholipid bilayer, select the list that most accurately predicts the relative rates of diffusion of these molecules (fastest to slowest) across a biological membrane. - alanine - propanol- sodium - estrogen
- Paramecium is a single-celled eukaryote that lives in fresh water. These organisms have one or more membrane-bound organelles called contractile vacuoles. These organelles allow the paramecium to expel excess water from the cytoplasm, which prevents the cells from bursting. Integral membrane proteins in the contractile vacuole membrane move hydrogen ions from the cytoplasm into the space inside the contractive vacuole. The movement of hydrogen ions into the vacuole by these integral membrane proteins requires ATP. Why does water move into the cytoplasm of the paramecium?
- The contractile vacuole is acidic compared to the cytoplasm of the paramecium. Therefore, the movement of hydrogen ions into the contractile vacuoles is an example of which of the following?
- The fluidity of cellular membranes is influenced by several factors including: (3 factors)
- Desaturases are enzymes that add double bonds to existing hydrocarbon chains, such as the fatty acids in membrane phospholipids. Now imagine that you are studying plant homeostasis in North Carolina, and you are particularly interested in seasonal changes in desaturase activity. Which of the following would you expect to observe with the onset of winter?
- Paramecium is a unicellular organism that lives in fresh water. Suppose you are studying two populations of this organism: one population lives in a pond in northern Ontario, Canada, and the other lives in a pond in southern Florida. If you examined the plasma membranes of both of these populations at the same time of year, what difference would you expect to find between the two populations' cell membranes?
- A dialysis bag was filled with 15% sucrose solution and placed in an unlabeled beaker filled with clear liquid. The dialysis bag was made of a semipermeable membrane that allowed the free passage of water but was not permeable to sucrose. After two hours the bag in the beaker increased in size and became turgid (firm). Based on this observation, the contents of the beaker could have been: a: 5% sucrose b: 15% sucrose c: 25% sucrose
- The movement of substances across a membrane by facilitated diffusion requires which of the following a: peripheral membrane proteins and ATP b: integral membrane proteins and ATP c: peripheral membrane proteins d: integral membrane proteins e: ATP
- A city government is attempting to reduce the digital divide between groups with differing access to computing and the Internet.Which of the following actions is least likely to be effective in this purpose?
- You notice that your browser is running a bit slow. Which of the followingsettings could be changed in order to increase your browsing speed?
- Water enters unicellular organisms that live in fresh water at a faster rate than it leaves because the cytoplasm of these organisms is ___________ compared to the freshwater environment outside the cell
- t/f: net diffusion stops once a solution is at equilibrium
- Solution A contains less dissolved solute than solution B. Therefore solution A is _________ compared to solution b?
- Client-server applications (8)A. are any apps that run on personal devices and need access to resources from a server.B. are distributed resources across multiple apps or devices.C. provide services such as data sharing and web pages.D. include database, file, mail, print, web, and game serversE. are also known as front-end and back-end applications.
- Which component of cell membranes attenuates (in other words reduces) the change in membrane fluidity as temperature increases or decreases?
- t/f: diffusion continues once a solution is set at equilibrium
- You plug in a new microphone into the USB port of your computer. Yourcomputer automatically picks up the microphone and installs the necessary drivers on its own. What kind of device is this microphone?