Which are electrical "nodes" of the heart? Check all that apply.

sinoatrial node

aortic node

lymph node

heart node

atrioventricular node

Which of the following protists gets nutrients mainly by absorbing molecules from other organisms through their cell walls and cell membranes? a. amoebas b. water molds c. ciliates d. slime molds

What will happen to a population of predators if there is a sudden, temporary increase in the number of prey? a. the population of predators will be uniform with no change. b. the population of predators will increase first and then decrease slowly. c. the population of predators will increase continuously.

Are these strong bases, neutral, strong acids, weak acids or weak base household bleach (ph=12.6) fluid in a car's battery (ph of less than 1.0) milk (ph=6.7) stomach contents (ph=2.2) pure water (ph=7)