1. Plant Cell Walls
1.1. Noncellulose polysaccharides harden the wall as the cell matures
1.2. Pectin
1.2.1. allow the walls to stretch as cells grow
1.2.2. abundant in the middle lamella, a layer of adhesive substances that holds cells together
1.3. Contain cellulose
1.4. Plasmodesmata
1.4.1. narrow channels that penetrate the cell wall to connect adjacent cells
1.4.2. Each channel contains a strand of cytoplasm
1.5. Cytoplasm
1.5.1. allows exchange of materials between cells.Only water and small solutes pass freely
1.5.2. connects all the cells within a plant
2. Endoplasmic Reticulum
2.1. Rough Endoplasmic Reticulum
2.1.1. Studded with ribosomes
2.1.2. Processing, folding and modification of proteins
2.2. Smooth Endoplasmic Reticulum
2.2.1. Has no attached ribosomes
2.2.2. Synthesizes phospholipids and steroids
3. Nucleus
3.1. Characteristics
3.1.1. Nucleoplasm
3.1.1.1. semifluid medium in the nucleus
3.1.2. Nucleolus
3.1.2.1. ribosomal RNA (rRNA) is made
3.1.3. Nuclear Envelope
3.1.3.1. double membrane that separates the nucleus from the cytoplasm
3.1.4. Nuclear pores
3.1.4.1. openings that permit transport of protein and ribosomal subunits
3.1.5. Chromatin
3.1.5.1. composed of DNA, protein, and some RNA
4. Ribosomes
4.1. Site of protein synthesis
4.1.1. Use messenger RNA (mRNA) as template
4.2. Composed of two subunits
4.2.1. Subunits consist of rRNA and protein molecules
4.3. Can be found
4.3.1. In groups of polyribosomes, several ribosomes associated with a single mRNA
4.3.2. attached to endoplasmic reticulum
4.3.3. free in cytoplasm