Some genetic disorders, such as sickle cell disease, are due to?

Me 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?

Which of the following human activities resulted in the growth of the north american deer population?

Which of the following was not a major animal on land during the carboniferous period? amphibians insects both a and b none of the above