Lecture notes – last week 1How does a cell interact with its environment? Feilim Mac Gabhann, Molecules and Cells, Fall 2013We must go beyond thinking of the cell as an isolated entity and begin to view cells in the context of the human body. What is the cell's environment? What does a cell interact with? How does it interact with and sense other cells, molecules and forces? How do the activities inside the cell – DNA replication, transcription, protein synthesis, signaling, molecular motors – come together to cause multicellular behaviors?
Alberts 4thEd, Figure 22-22 A. CELLS OF THE VASCULAR SYSTEMEndothelial cellsform the lining of the entire circulatory (vascular) system including the heart and all blood vessels – arteries, veins and capillaries. Their apical side faces the lumen of the blood vessel (i.e. is in contact with the bloodstream) while their basal side is in contact with the basal lamina component of the basement membrane. Beyond the basement membrane, endothelial cells are surrounded by smooth muscle cells (in arteries and veins) or pericytes (in capillaries). Endothelial cells typically align and elongate in the direction of blood flow, as shown below in response to shear stress– a : Izumo et al. JAMA. 1999. Make sure you understand and can define all words in bold italics