BIO251H1 Lecture Notes - Lecture 1: Pith, Cuticle, Cytoskeleton
Document Summary
Plant cell composed of 2 components: cell wall, protoplast. The primary cell wall is composed of cellulose microfibrils in a matrix. 2 types of walls to consider: primary wall, secondary wall. Primary wall = first cell wall to be laid down during development. Every plant cell has a primary wall but not every plant cell has a secondary wall. Cellulose is the most abundant component in the cell wall (re-bar structure) Pectins also integrated within matrix of hemicellulose and cellulose: pectin very hydrophilic, keep primary wall very moist. Turgor provides structural support for physiologically active cells. When cellulose is made, it is a chain of glucose molecules (6-carbon molecules) that make up the most basic element of cellulose. In diagram, 3 chains of cellulose molecules are bonded together via h-bonds: h-bonds makes the chains really strong. Cellulose microfibrils made of chains of cellulose are synthesized by an enzyme inside plasma membrane.
