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Andromeda215 wrote:answers?
[hide]|1. Quickly conduct an action potential from cardiomyocyte to cardiomyocyte
2. Sinusoids --> central vein--> hepatic vein --> inferior vena cava --> RA
3. Foramen ovale
4. Descending limb is only permeable to water. Hyperosmotic medulla makes it so that the water in filtrate at that point gets reabsorbed. Ascending limb is not water permeable, and contains active transporters and symporters that send certain ions from filtrate to medulla, creating that hyperosmotic environment that allows the water reabsorption in the descending limb to take place.
5. In the heart epinephrine/norepinephrine binding causes faster heart rate and stronger contraction. In the vessels, the effect can vary depending on whether there's more epinephrine or norepinephrine acting (vasodilation or vasoconstriction). This is contradictory because in the heart epinephrine and norep cause the same effects, while in vessels, it's different.[/hide]

Andromeda215 wrote:Thanks! sorry about doing the hide feature wrong.
Yeah so really from what i know theres alpha, beta1, and beta2 receptors. Binding of alpha receptors tends to cause vasoconstriction, binding of beta2 receptors causes vasodilation, and binding of beta1 causes increased contractability and HR. Epinephrine preferentially binds to beta receptors (1 and 2). Norepinephrine preferentially binds to alpha.
Only beta1 receptors are found in the heart, so no matter whether epinephrine or norepinephrine actually bind to those receptors, the effect is the same.
But in skeletal muscle arteries, alpha and beta2 are found. So whether overall vasoconstriction or vasodilation happens depends on how much epinephrine or norepinephrine is around at the time. More epinephrine (like during exercise) means overall, more beta2 receptors are bound, which means on average more vasodilation happens, which is good bc more blood flow to tissue that needs it.
hopefully that made sense

Andromeda215 wrote:1. What hormone most typically stimulates RBC production?
2. Are arteries or veins larger in diameter? why?
3. What is anemia?

1. hemopoietin 2. Veins.  Arteries must be narrow in diameter because there is high pressure blood that must be maintained/carried 3. Anemia is a general term for several specific disorders where in one way or another, oxygen cannot adequately reach tissues, whether through an iron deficiency or misshapen erythrocytes.

sophisSyo wrote:

Andromeda215 wrote:1. What hormone most typically stimulates RBC production?
2. Are arteries or veins larger in diameter? why?
3. What is anemia?

My answers (Click to Show Hidden Text)

1. hemopoietin 2. Veins.  Arteries must be narrow in diameter because there is high pressure blood that must be maintained/carried 3. Anemia is a general term for several specific disorders where in one way or another, oxygen cannot adequately reach tissues, whether through an iron deficiency or misshapen erythrocytes.

sophisSyo wrote:

My questions (Click to Show Hidden Text)

1) During hemostasis, what is the difference between intrinsic pathway and extrinsic pathway? 2) For the embryo, what do liver-spleen produce from mesenchyme? 3) How do blood volume and systematic vascular resistance compensate for heart failure?

1) The extrinsic pathway is initiated by foreign injury when the blood touches the damages tissue. The intrinsic pathway doesn't need an external injury. It is initiated when there is damage inside the vascular walls. 2) RBCs? 3)Increase in blood volume compensates for heart failure and increases stroke volume so that more blood reaches the tissues. Resistance also increases(vasocontriction) to maintain blood pressure because BP usually is less due to reduced CO caused by heart failure.

gillio wrote:

sophisSyo wrote:

My questions (Click to Show Hidden Text)

1) During hemostasis, what is the difference between intrinsic pathway and extrinsic pathway? 2) For the embryo, what do liver-spleen produce from mesenchyme? 3) How do blood volume and systematic vascular resistance compensate for heart failure?

My answers (Click to Show Hidden Text)

1) The extrinsic pathway is initiated by foreign injury when the blood touches the damages tissue. The intrinsic pathway doesn't need an external injury. It is initiated when there is damage inside the vascular walls. 2) RBCs? 3)Increase in blood volume compensates for heart failure and increases stroke volume so that more blood reaches the tissues. Resistance also increases(vasocontriction) to maintain blood pressure because BP usually is less due to reduced CO caused by heart failure.

reticulo-endothelial cell, which is the parent cell for all blood cells