BIOL 120: Principles of Biology

Discover the dynamic nature of the cell's lipid bilayer. Delve into the roles of unsaturated and saturated phospholipids in membrane fluidity. Understand temperature's influence on this vital cellular component.

Explore the role of human placental lactogen (hPL) in this informative video. Learn how hPL prepares the breasts for lactation, debunking other hypotheses about its functions in nourishing the placenta or regulating the menstrual cycle. Discover the primary function of this remarkable placental hormone.

Explore the intricacies of muscle contraction and the pivotal role played by elements like Calcium, Sodium, Potassium, and Chloride. Learn how Calcium directly triggers contraction by interacting with troponin and actin filaments. A thorough breakdown of each element's unique contribution to our body's movement.

Discover the concept of adaptation in this video, where we evaluate four scenarios to determine which represents a heritable trait enhancing an organism's survival in its environment. Learn how the webbed feet of a duck exemplify a true adaptation, enabling it to thrive in its habitat.

Discover the intricacies of synovial joints, the body's most moveable joint type. Explore the role of articular cartilage, joint cavities, and the articular capsule in ensuring smooth movement. Gain insights into the varying presence of fibrocartilage in different synovial joints.

Learn about the composition of arteries focusing on those closer to the heart. Understand the role of endothelium smooth muscle fibers elastic fibers and collagen in these arterial structures. Discover why arteries near the heart have a higher percentage of elastic fibers to withstand pressure changes effectively.