BIOL 1410 Lecture 3: 3 - TOPIC III - CELLULAR LEVEL OF ORGANIZATION

• School: University of Manitoba
• Department: Biological Sciences
• Course: BIOL 1410
• Professor: Paul Messing

Document Summary

Basic structural and functional unit of the body. Atom loses e-(s): becomes a +ve ion (cation: principal parts of the cell, cell membrane / plasma membrane / plasmalemma. Composed of: phospholipid bilayer, phosphate head group (hydrophilic, fa tails (hydrophobic, divides icf + ecf. Extracellular fluid (ecf) = outside cell: cholesterol, scattered throughout membrane, adds stability to the cell membrane. 2 types: membrane proteins i. integral proteins. Within the membrane have a hydrophobic region some extend across entire membrane = transmembrane: peripheral proteins. Attached to either surface of integral proteins. 1 identity markers (for immune system: membrane carbohydrates. Bound to proteins (glycoproteins) or lipids i. cell recognition (e. g. egg and sperm: microvilli anchor cells together ii. small projections of cell membrane. Best seen on cells of the small intestine and kidney. Fluid mosaic model of the cell membrane: Fluid - membrane constituents can move around (phospholipids + some proteins) Mosaic proteins dot surface like tiles in a mosaic.