University of Central Florida (UCF) BSC2010C Biology I Practice Exam 2

The term that describes a molecule possessing both hydrophilic (water-attracting) and hydrophobic (water-repelling) properties is amphipathic. This characteristic is particularly important in biological systems. Amphipathic molecules, such as phospholipids, have a hydrophilic "head" that interacts well with water and hydrophobic "tails" that avoid water, which is crucial in the formation of cell membranes. The unique arrangement allows these molecules to form bilayers that make up cellular membranes, facilitating the compartmentalization of biological processes.

Hydrophobic refers solely to the properties that repel water, while hydrophilic pertains exclusively to water-attracting characteristics. An "integral" molecule usually refers to proteins embedded within a cell membrane, but does not inherently describe the dual properties of being both hydrophilic and hydrophobic. Therefore, amphipathic is the correct term to convey the presence of both types of properties in a single molecule.