They contain carbon, hydrogen, oxygen and nitrogen and usually sulfur, occasionally phosphorus. Proteins form a large and essential part of the body mass, comprising especially cell membranes, connective tissue, muscles, enzymes, hormones, blood proteins. To maintain this mass the diet must contain a high proportion of protein, especially in growing animals and those recovering from debilitating diseases.
Russian composer Sergei Prokofiev wrote Peter and the Wolf in 1936 after returning to Moscow following a 19-year, self-imposed exile. It is a children's musical story that teaches about the orchestra by introducing various characters portrayed by seven themes played on either solo instruments or groups of instruments.
The inspiration for Peter came from a Life magazine photo article from 1940, and Keats' desire to have minority children of New York as central characters in his stories. Peter appears in six more books growing from a small boy in The Snowy Day to pre-adolescence in A Letter to Amy. 1 Life and career.