What are responsible for contraction and relaxation in muscles? a) contractile proteins b) contractile vacuoles c) fat globulesWhat are responsible for contraction and relaxation in muscles? pls fast thanks

Pls in your opinion, what are the limiting factors that might affect the growth or diversity of our ecosystem? respond to this question in claim, evidence, reasoning format. 1. make your claim (i are the limiting factors that might affect the growth or diversity of our 2. follow the claim with 3 pieces of evidence. evidence may be taken from the reading, the videos, previous lessons, or googled answers. site sources, too. 3. use reasoning to explain why you chose your evidence.