What are the main components needed to insure ecosystem stability? a.
estuary, savanna, and tundra
b.
primary and secondary succession
c.
food, water, shelter and biodiversity
d.
moderate climate, sufficient space, and adequate sunli

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.

Ascientist is studying muscle twitches in chicken quadriceps. to activate the muscle, he needs to provide stimulus to the

How can you approximate the number of calories required to keep you in energy balance?