Compounds released from cells that influence the same cell are called . Select one: a. paracrine chemical messengers b. steroidal hormones c. neuropeptides d. tropic hormones e. autocrine chemical messengers

Aboy jumps into a cold swimming pool and his body tempature goes down hus muscles ,blood vessels

Which of the follow describes a disadvantage secondary sources have compared to primary sources?

20 point pls brianliest 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?