Complete the Concept Map to describe ionic movement during action potentials in cardiac pacemaker and contractile cells, and trace the conduction pathway. Drag the appropriate labels to their respective targets. AV nodes, bundles, branches, and Purkinje fibers -are specifically made of → directly trigger atria to contract and activate Ca2+ ions directly trigger ventricles to contract and activate cardiac muscle fibers enter plateau phase due to slow influx of K ions rapidly depolarize due to influx of Na ions pacemaker cells -repolarize due to efflux of → slowly depolarize due to influx of SA nodes

She planned to observe the flowers for the next five days for an hour at the same time each afternoon. then she wou the data in a multiple line graph to compare the number of bees that visited each flower. which statement best descr data in this investigation?

80 points pls brainliest 1. what does a red shift mean? blue shift? 2. describe the big bang theory. according to this theory, how old is the universe? 3. scientists believe the universe is expanding. what is the evidence that supports this? 4. describe a nebula. 5. describe the 3 types of galaxies. what is a barred spiral galaxy? 6. what is a light year? how far is alpha centauri from earth? 7. describe the universal law of gravitation. be sure to include gravitational force between two objects. 8. describe the planets’ orbits around the sun. 9. what is the asteroid belt? where is it located? 10. describe rotation and revolution of earth. what determines an earth day and year? 11. how do galaxies exist? 12. compare and contrast the inner and outer planets. 13. what causes the seasons?

If a grape were placed in a hypertonic solution what would happen and why?