Chapter 6: Endomembrane System

Golgi Apparatus

"Warehouse" for receiving, sorting, and shipping products of the ER such as protein. (Modification of lipids and proteins into vesicles. These vesicles migrate and merge with the Plasma membrane, [and other organelles] releasing their contents outside of cell)

Vesicles

(Sacs made of membrane) That are a part of the continuity of the Endomembrane System. They typically carry different materials throughout the system.

Lysosomes

A membranous sac. Of digestive enzymes (hydrolytic enzymes) that hydrolyze macromolecules. The enzymes and membrane found here are produced within Rough ER and are transported to the Golgi Apparatus for further processing. These vesicles generally bud from the Golgi Apparatus. They notably contain an acidic PH, and are neutralized In the neutral PH of the Cytosol if one breaks open. These carry out the processes of Autophagy, continually renewing the cell.

Endoplasmic Reticulum

Consists of membraneous tubules and sacs called cisternae. The membrane seperates the ER lumen (internal) from the cytosol. It is continuous with the nuclear envelope.

Central Vacuole (Plant Cell)

Develops by coalescence of smaller Vacuoles. (The fluid inside; Cell sap, is the cell's main repository of inorganic ions.) It plays a major role In the growth of plant cells, which enlarge as it absorbs water.

Phagocytosis

Food vacuoles getting consumed by lysosomes. (Process of digestion)

Food Vacuoles

Formed by phagocytosis. (plasma membrane pinching off nutrients to digest with the lysosome)

Endomembrane System (Structures)

Includes the nuclear envelope, Endoplasmic reticulum, the Golgi Apparatus, Lysosomes, Vesicles and Vacuoles, and the Plasma membrane.

Smooth ER

Lacking of ribosomes. Functions in diverse metabolic processes. (Synthesis of lipids, metabolism of carbohydrates, detoxification of drugs and poisons, storage of calcium ions)

Vacuoles

Large vesicles derived from the ER and Golgi Apparatus. Like all cellular membranes, the vacuolar membrane is selective in Transporting solutes. Meaning its internal composition is different from that of the Cytosol. (different internal fluid essentially)

Glycoproteins

Proteins covalently bonded to carbohydrates

Transport Vesicles

Proteins surrounded by membranes that transfer materials from ER (budding from the transitional ER) to the Golgi apparatus.

Rough ER

Studded with Ribosomes. Cells secrete the protein produced by ribosomes here. (Insulin for example). Essentially a factory for membrane production.

Endomembrane system (Function)

Synthesis of proteins, transport of proteins to membranes/out of cell, Metabolism, movement of lipids, detoxification of poisons.

Cisternae

The Endoplasmic Reticulum consists of a network of membranous tubules and sacs called:

Contractile Vacuoles

They Pump excess water out of the cell to maintain a suitable concentration of ions and molecules in the cell.

Transitonal ER

Where the transport vesicles bud off from the Endoplasmic Reticulum.