1. Whats a difference and a similarity between
the Water Cycle & Carbon Cycle?

6. in the dna double helix, how are the two strands of dna held together? a. chemical bonds between base pairs hold the two strands of dna together. b. hydrogen bonds between the base pairs hold the two strands of dna together. c. hydrogen bonds between sugar groups and phosphate groups hold the two strands of dna together. d. chemical bonds between sugar groups and phosphate groups hold the two strands of dna together.

What does it mean for a cell membrane to be selectively permable

What is the primary goal of human communities?