The flow of energy through living systems can be modeled as food chains, food webs, or energy pyramids. The energy organisms need to live and grow first enters the ecosystem when which of the following occurs? 1.Plants take in light energy from the sun. 2. Decomposers break down dead organisms 3.Primary consumers eat plants for food 4. Secondary consumers eat primary consumers

You have just sequenced a new protein found in mice and observe that sulfur-containing cysteine residues occur at regular intervals. what is the significance of this finding? it will be important to include cysteine in the diet of the mice. cysteine residues are required for the formation of α helices and β pleated sheets. cysteine residues are involved in disulfide bridges that form tertiary structure. cysteine causes bends, or angles, to occur in the tertiary structure of proteins.