How do cells in a multicellular organism maintain homeostasis as compared to individual cells maintaining homeostasis?

In dna, only the_ varies from one nucleotide to another. base phosphate sugar amino acid

Some birds look for food near cattle and other livestock. the movement of the cattle churns up the ground, making insects available to the birds. the cattle appear to be unaffected by the presence of the birds. what kind of relationship exists between the birds and the cattle? o a. parasitism o b. commensalism o c. predation o d. mutualism

What is the next step in muscle contraction after the actin changes shape? (apex)