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 structure of eukaryotic cellsCompare animal cells with plant cellsState the role of the plasma membraneSummarize the functions of the major cell organelles
The phospholipid bilayer is the fundamental structure which makes up the cell membrane. It is made of 2 sheets of phospholipid molecules which are said to have hydrophillic heads and hydrophobic tails. Therefore molecules on opposite sheets face back to back to protect their hydrophobic area from the surrounding intra or extracellular fluid. This creates a region inside the membrane which is hydrophobic.