Which of the following best describes the components of the DNA twisted ladder? A. The sides are made of alternating polypeptide chains, and the rungs are made of amino acid segments joined by
hydrogen bonds

B. The sides are made of alternating amino acids, and the rungs are made of polypeptide chains joined by hydrogen bonds.

C. The sides are made of alternating phosphate-sugar groups, and the rungs are made of complementary nitrogenous
bases joined by hydrogen bonds

D. The sides are made of alternating nitrogenous bases, and the rungs are made of phosphate-sugar groups joined by hydrogen bonds

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?