BIOLOGY 2B03 Lecture 2: BIO 2B03 - JAN 26, 2017
27 Jan 2017
School
Department
Course
Professor
Document Summary
Membranes = barrier to protect cell from external environment. The barrier is made so that hydrophobic and hydrophilic part is enclosed by hydrophilic heads that creates barrier preventing molecules from crossing without specific properties. There are points of contact and channels that allow movement. Needs membrane flexibility allowing some things in and some out. Lipid component - like an island within a sea. Limitation = the detection -- too small to see and therefore controversial until able to detect the components. Selective permeability = makes membranes what they are. Muscle cell -- bigger the membrane, bigger the muscle cell. Cell-cell interactions -- things that allow physical interaction or ionic. Proposed that membrane cross-section = sea of phospholipids with hydrophilic head and hydrophobic tail -- they create a bilayer. Sea of lipids are embedded with proteins (transmembrane/peripheral) Flipping is not allowed (not easy to happen)
