The average distance between earth and the sun is known as a(n)

a. light-year
b. astronomical unit
c. big bang
d. aphelion

Which short-term environmental changes would a very small asteroid or comet impact on earth most likely cause? check all that apply. flooding extinction craters on surface changes in weather patterns death of organisms and populations

Which of the following molecules could pass through the plasma membrane by simple diffusion? a. na+ ions b. glucose c. amino acids d. carbon dioxide

Describe the process of nociception using the four phases of