1. Draw a picture of a cell located in the intestines for yourselfand label the surfaces and draw the location of the differentreceptors found on the plasma membranes. Then explain in your ownwords to turn in all of the different carrier proteins involved inthe reabsorbtion of sodium and glucose from the intestinal mucosato the blood.
2. What is the functional significance of tight junctions? Reflecton the fact that this is the same system involved in the kidneysfor the reuptake of sodium and glucose in the kidney tubules. Whyis that important to consider?
3. Draw a picture of a parietal cell located in the stomach foryourself. What protein carriers are important in the production andsecretion of HCl in the stomach. How is this process influenced bycarbon dioxide transport on the erythrocyte plasma membrane?
4. What is the importance of solute concentration on the reuptakeof water in animal and plant cells?
5. How do vacuoles work? What is the importance of V-class H+ATP-ase pumps in the uptake of water?
6. Channel proteins are typically involved in the import of ionsacross the plasma membrane. What are the major characteristics ofpotassium leak channels?
7. What is the importance of the water of hydration in theimportance of movement of ions, like potassium, through channelproteins?
8. How is the Na+/K+ ATP-ase critical in the re-establishment ofthe resting membrane potential across the plasma membrane of animalcells.
9. How do voltage-gated ion channels work in the venus flytrap.
10. In anatomy and physiology, we discussed how nerve signalstravel to the cochlear nerve allowing us to hear. Using yourknowledge of anatomy and the information provided on the powerpoint slides provided to you explain the role of stress-activatedchannels in this process.
11. Cholera toxin, a pathogenic intestinal bacterium, causes anindirect reduction in the activity of the Na+/K+-ATPase inintestinal epithelial cells. This results in reduced uptake ofsmall sugars and amino acids from the intestine, as well as severediarrhea. How are these two problems (eg. reduced nutrient uptakeand diarrhea) coupled to impaired Na+/K+- ATPase function?
12. Like animal cells, the plasma membrane of plant cells has amembrane potential and plant cells also use cation-based symportfor nutrient uptake. However, plant cells do not have Na+/K+-ATPasein their plasma membranes. Explain, then, how they establish andmaintain a membrane potential and how they co-import nutrients inthe absence of the Na+/K+ pump. Also explain how plant cell volumeis regulated in light of this major difference.