Difference Between An Organelle And A Complex

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DQ #3. What is the difference between an organelle and a complex? Describe 4 organelles and/or complexes found in the cytoplasm. An organelle is surrounded by a membrane, where as a complex is not surrounded by a membrane. Together the organelles and complexes make up a cell along with the nucleus which are all contained within the cytoplasm of the cell. Organelles of the cell include the endoplasmic reticulum, Golgi apparatus, mitochondria, and lysosomes. Complexes of the cell include ribosomes and proteasomes. Ribosomes are small particles of rRNA and proteins that are held together by mRNA. Ribosomes in the cell are either attached to the endoplasmic reticulum or are free. Free ribosomes take part in the synthesis of proteins that remain in the cell. Those attached to the ER translate mRNAs that code for proteins to be bound in membranes or for secretion. The endoplasmic reticulum (ER) is a changing system of interconnected membranous tubes and sac-like cisternae. Within the lumen, cavity within the tubes, of the ER is a matrix that connects the space between the two membranes of the nuclear envelope to the cell rim. The functions of the ER is communication system for transporting various substances from one part of the cell to another. The ER membranes have a large surface area in which many enzyme systems are attached to it that provide the supplies for many cellular metabolic functions. There are two different forms of endoplasmic reticulum: rough and smooth. The rough
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