What fact explains why tundra biomes remain cold year-round but taiga biomes have alternating warm and cold season?

Hummingbirds drink nectar from flowers, while robins eat plant seeds. what does this reduce?

Stephen is a student who wants to test his knowledge of medical terminology. which option could he use?

Dna and rna share a number of similarities, but they also differ in certain aspects of their structure. wich nitrogenous base is found in rna but is not found in dna