Few Questions week before exam

[NVswmmr]

1. What are the basicity trends on the periodic table? I've heard both going down to the left and down to the right.
2. Why does the pressure increase in the left ventricle increase and the pressure in the right ventricle decrease? The reasoning behind it in the book was that systemic resistance increases, why is this? Shouldn't it take an increase in pressure to inflate the lungs instead of shunting the blood?
3. Are microvilli cells made of only 1 layer of epithelial cells and 1 layer of basement membrane cells? Is there more than 1 cell layer b/t the aplical and basolateral side (since the depictions show a single cell when showing tight junctions, is there then a space between the basolateral side and the basement membrane?)
4. Given that cortisol is meant to respond to stress, why then does it trigger glycogen production? Isn't this counterproductive to its other effect (gluconeogenesis) since glycogen production is also a result of insulin?
5. How is the complement system for the immune response nonspecific if as shown in the humoral response, the complement system is specific?

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[plsfoldthx]

1. What are the basicity trends on the periodic table? I've heard both going down to the left and down to the right.
2. Why does the pressure increase in the left ventricle increase and the pressure in the right ventricle decrease? The reasoning behind it in the book was that systemic resistance increases, why is this? Shouldn't it take an increase in pressure to inflate the lungs instead of shunting the blood?
3. Are microvilli cells made of only 1 layer of epithelial cells and 1 layer of basement membrane cells? Is there more than 1 cell layer b/t the aplical and basolateral side (since the depictions show a single cell when showing tight junctions, is there then a space between the basolateral side and the basement membrane?)
4. Given that cortisol is meant to respond to stress, why then does it trigger glycogen production? Isn't this counterproductive to its other effect (gluconeogenesis) since glycogen production is also a result of insulin?
5. How is the complement system for the immune response nonspecific if as shown in the humoral response, the complement system is specific?

1. More electronegative = weaker base. Remember, lewis base is electron donating.
2. No idea what you're asking here. I don't know what pressure in ventricles has to do with pulmonary pressure.
3. I don't know, but I'm sure this is beyond the scope of the MCAT.
4. You need glucose to make glycogen
5. Again, you need to word this question better. You're asking why is complement system nonspecific if it's specific. My understanding is that complement can act both specifically and nonspecifically.

 

[NVswmmr]

I apologize for not being clear. Let me rephrase two of the questions.

For #2, a question in the book said that since when a fetus is in the womb, the blood shunts from the right to left part of the heart because the lungs are not inflated/nonfunctioning. It then goes on to ask what the greatest pressure differential would be between right before birth and right after birth in regards to the pressures in the chambers of the heart (after the lungs of the newborn becomes functional). The answer it gave was that the largest pressure difference would be in the left ventricle because of the "resistance increases through the systemic circulation as a result of the loss of blood flow through the placenta; the increase in resistance means that pressure in the left ventricle increases while the pulmonary artery, right atria and right ventricle decreases". So I'm wondering why it doesn't take a greater change in the right ventricle due to lung inflation and why resistance would increase from loss of placenta.

For #4, I'm questioning the effect of cortisol on glycogen production. My understanding is that insulin will stimulate glycogen production in the liver from free glucose. Cortisol, however, seems to form free glucose from the liver (from gluconeogenesis) as well as form glycogen, which I thought would decrease blood glucose concentrations. These two actions of cortisol seem to be counterproductive.

Thanks!

 

[joshto]

For #4, cortisol does not stimulate glycogen formation; rather, cortisol activates glycogen breakdown, as well as Gluconeogenesis--both of these cortisol actions have the effect of increasing blood glucose.