Although your answer is correct for 1, the main function of intercalated discs in the cardiac muscle is to make sure that each cell in atrial myocardium and the ventricular myocardium contract together as a syncytium. All the other ones look right . Also, you forgot to put the | right after the [hide] when you began answering the question and that is why your answers weren't hidden.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]
Quick question: can epinephrine and norepinephrine both be vasoconstrictors and vasodilators in blood vessels? Or is one strictly a vasoconstrictor and the other a vasodilator, and depending upon the quantity of each, vasoconstriction or vasodilation occurs? Your wording kinda confused me