General Physiology Review Flashcards
You order a blood test. When you receive the lab report there is a note that the blood was lysed when it was drawn. Which of the following readings could be erroneously (incorrectly) elevated?
Potassium because you have high potassium inside the cells, and if the RBCs are all lysed, then you will have a high potassium level just floating around
Which of the following would require energy? A) Na into cell B) glucose into cell C) K into cell D) chloride into cell
Potassium into cell (c)
Sodium, chloride, and bicarb are where primarily?
ECF
Would lysing RBCs have an affect on the extracellular concentration of:
1) sodium
2) potassium
3) chloride
4) bicarb
1) no
2) yes!
3) no
4) no
If we open up a sodium channel on the cell membrane, which way does it flow?
Into the cell
How often do cells need glucose?
All the time. They are pretty much starved for it at all times. Therefore, it won’t really need energy to get into the cells
Where is there a lot of chloride?
ECF (outside the cell)
What would cause the membrane potential to become more negative?
Closure of sodium leak channel
What would closing of a potassium leak channel do to the cell?
Trapping positive charge (potassium) inside cell, making it more positive
What would closing of a chloride leak channel do to the cell?
Chloride wants to move into cell, adding negative charges, making membrane potential more negative if it is open; if it is closed, it will be less negative b/c we are stopping the addition of negative charges
What would closing of an aquaporin channel do to the cell?
Won’t move water..who cares?
What would closing of a sodium leak channel do to the cell?
Sodium moves into the cell, adding positive charges into the cell, making it more positive; if this is closed, it would make it more negative
Closure of what channel is very important in phototransduction?
Sodium channel
Which junction is the most restsrictive celllular junction?
Tight junction
What makes up gap junctions?
6 connexins
Where are gap junctions found?
Smooth muscle
(Where you have to have very coordinated movement)
Vascular muscle (bladder, gut)
Are gap junctions chemical or electrical junctions?
Electrical
Structural spot-welds for support
Anchoring junctions
Cell-to-cell anchoring junctions
Desmosomes
Cell to ECM anchoring junctions
Hemidesmosomes
Areas where tight junctions are found
Eye, brain, testes
Junction where cell membranes touch, and are super restrictive, where most movement is transcellular
Zonula occluden
Where are zonula occludens found?
Blood-brain barrier
Junction where the space between cellular membranes varies and filtration can occur
Zonula adherens
