Chapter 3 (part c) provides knowledge of the cytoplasm. This chapter describe the composition of the cytosol; discuss the structure and function of mitochondria; discuss the structure and function of ribosomes, the endoplasmic reticulum, and the Golgi apparatus, including functional interrelationships among these organelles; compare the functions of lysosomes and peroxisomes. | Cells: The Living Units: Part C Located between plasma membrane and nucleus Cytosol Water with solutes (protein, salts, sugars, etc.) Cytoplasmic organelles Metabolic machinery of cell Inclusions Granules of glycogen or pigments, lipid droplets, vacuoles, and crystals Membranous Mitochondria Peroxisomes Lysosomes Endoplasmic reticulum Golgi apparatus Nonmembranous Cytoskeleton Centrioles Ribosomes Double-membrane structure with shelflike cristae Provide most of cell’s ATP via aerobic cellular respiration Contain their own DNA and RNA Figure Enzymes Matrix Cristae Mitochondrial DNA Ribosome Outer mitochondrial membrane Inner mitochondrial membrane (b) (a) (c) Granules containing protein and rRNA Site of protein synthesis Free ribosomes synthesize soluble proteins Membrane-bound ribosomes (on rough ER) synthesize proteins to be incorporated into membranes or exported from the cell Interconnected tubes and parallel membranes enclosing cisternae Continuous with nuclear membrane Two varieties: Rough ER Smooth ER Figure Nuclear envelope Ribosomes Rough ER Smooth ER (a) Diagrammatic view of smooth and rough ER External surface studded with ribosomes Manufactures all secreted proteins Synthesizes membrane integral proteins and phospholipids Tubules arranged in a looping network Enzyme (integral protein) functions: In the liver — lipid and cholesterol metabolism, breakdown of glycogen, and, along with kidneys, detoxification of drugs, pesticides, and carcinogens Synthesis of steroid-based hormones In intestinal cells—absorption, synthesis, and transport of fats In skeletal and cardiac muscle — storage and release of calcium Stacked and flattened membranous sacs Modifies, concentrates, and packages proteins and lipids Transport vessels from ER fuse with convex cis face of Golgi apparatus Proteins then pass through Golgi apparatus to trans face Secretory vesicles leave trans face of Golgi stack and move to designated parts of cell Figure Protein- containing . | Cells: The Living Units: Part C Located between plasma membrane and nucleus Cytosol Water with solutes (protein, salts, sugars, etc.) Cytoplasmic organelles Metabolic machinery of cell Inclusions Granules of glycogen or pigments, lipid droplets, vacuoles, and crystals Membranous Mitochondria Peroxisomes Lysosomes Endoplasmic reticulum Golgi apparatus Nonmembranous Cytoskeleton Centrioles Ribosomes Double-membrane structure with shelflike cristae Provide most of cell’s ATP via aerobic cellular respiration Contain their own DNA and RNA Figure Enzymes Matrix Cristae Mitochondrial DNA Ribosome Outer mitochondrial membrane Inner mitochondrial membrane (b) (a) (c) Granules containing protein and rRNA Site of protein synthesis Free ribosomes synthesize soluble proteins Membrane-bound ribosomes (on rough ER) synthesize proteins to be incorporated into membranes or exported from the cell Interconnected tubes and parallel membranes enclosing cisternae Continuous with nuclear membrane Two .
