How does the immune system work together with the circulatory system to function properly? a. the white blood cells of the immune system fight and destroy pathogens. b. red blood cells move through the body (to parts where they are needed) in the blood vessels of the circulatory system to fight infection. c. the infection site receives oxygen-depleted blood from the circulatory system's arteries, so the immune system works harder. d. pathogens released by immune cells cause increased blood flow to the infection site, which brings other pathogens to the area more.

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?