In the introduction to the article, the authors write "soon after the expansion of molecular biology in the 1950’s, it became evident that by comparing proteins and nucleic acids of one species with those of another, one could hope to obtain a quantitative and objective estimate of the "genetic distance" between species". what did the authors mean? how do you "compare proteins and nucleic acids" (or how did you in 1975 when this article was written)?

When is your respiration rate likely to change? a. when your intestines are digesting b. when your cells have too much glucose c. when your cells need more oxygen d. when your liver is working after a meal

In the water cycle , when does water undergo a chemical change

Refer to this portion of a dichotomous key for fish identification to answer the question. 1. (a) has a single dorsal fin ® 5 (b) has a double dorsal fin ® 2 2. (a) one fin is spiny, the other is smooth ® 3 (b) one fin is not spiny or smooth ® 4 5. (a) has small fin on back near tail ® 6 (b) has no fin on back near tail ® 7 6. (a) has barbs near the mouth ® catfish (b) does not have barbs near the mouth ® 10 7. (a) tail is asymmetrical ® 8 (b) tail is symmetrical ® 9 10. (a) scales are small ® trout (b) scales are large ® whitefish what is the next step to complete to identify a fish that has a single dorsal fin, no fin on the back near the tail, and no barbs near the mouth? step 2 step 5 step 7 step 10