Students learn that fats found in the foods we eat are not all the same; they discover that physical properties of materials are related to their chemical structures. Provided with several samples of commonly used fats with different chemical properties (olive oil, vegetable oil, shortening, animal fat and butter), student groups build and use simple LEGO MINDSTORMS(TM) NXT robots with temperature and light sensors to determine the melting points of the fat samples. Because of their different chemical structures, these fats exhibit different physical properties, such as melting point and color. This activity uses the fact that fats are opaque when solid and translucent when liquid to determine the melting point of each sample upon being heated. Students heat the samples, and use the robot to determine when samples are melted. They analyze plots of their collected data to compare melting points of the oil samples to look for trends. Discrepancies are correlated to differences in the chemical structure and composition of the fats.

Biology is designed for multi-semester biology courses for science majors. It is grounded on an evolutionary basis and includes exciting features that highlight careers in the biological sciences and everyday applications of the concepts at hand. To meet the needs of today’s instructors and students, some content has been strategically condensed while maintaining the overall scope and coverage of traditional texts for this course. Instructors can customize the book, adapting it to the approach that works best in their classroom. Biology also includes an innovative art program that incorporates critical thinking and clicker questions to help students understand—and apply—key concepts.

By the end of this section, you will be able to:Describe the four major types of lipidsExplain the role of fats in storing energyDifferentiate between saturated and unsaturated fatty acidsDescribe phospholipids and their role in cellsDefine the basic structure of a steroid and some functions of steroidsExplain the how cholesterol helps to maintain the fluid nature of the plasma membrane