Complete the following sentence.

Polyculture and permaculture methods reduce many agricultural tasks, limiting the soil that can result
from mechanical cultivation and from foot traffic, which is particularly useful when cultivating soils with a high clay or silt content.

What is thought to have caused the mass extinction at the end of the cretaceous period?

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.

Identify two examples of chemical reactions that you have encountered during the last week. identify an exothermic and endothermic reaction. explain.