Bookings for the quarter were $221.8 million, up 16% from Q1 of 2011 and up 9% from Q4’s net order total. Our recent acquisitions contributed less than 3% of bookings. Don will discuss the makeup of orders in our markets in a moment. Changes in currency rates had a small impact in our orders in totals and backlog this quarter. At the end of the latest quarter, the euro was $1.33 compared to $1.29 at the end of Q4. The backlog at the end of the quarter was $434.9 million and represents about 6 months of revenue at our current run rate.
Moving to slide four, first quarter revenue was up 10.5% from a year ago and 2% from the fourth quarter. Compared with a year ago, less than 2% of our revenue growth came from acquisitions offset in part by less than a 1% reduction due to changes in foreign exchange rates. Revenue growth was driven by Electronics segment, which was up 27% from last year’s first quarter and 42% from the fourth quarter of 2011 and made up 36% of the total.
The Electronics segment also had a strong bookings and a book-to-bill ratio of 1.12 for the quarter. Materials Science segment revenue of $73.2 million was up 4% from the first quarter of 2011 and down 20% on a normal seasonal basis from a record level fourth quarter of 2011. Within this segment, natural resources revenue was up 30% compared with last year’s first quarter and material science research revenue was flat.