Defra Structures and who does what

http://download.cabinetoffice.gov.uk/structure/Defra-Organisation-Chart.pdf

For the inquisitive the second Cabinet site gives salaries and stuff  also does other depts.

http://www.cabinetoffice.gov.uk/newsroom/news_releases/2010/101015-structure-charts.aspx

For science and innovation see the BIS

http://download.cabinetoffice.gov.uk/structure/bis-org-chart.pdf