Unit 2: Cell Structure and Function

prokaryotic cells

• found in domains bacteria and archaea

• single circular chromosome found in nucleoid

• no membrane bound organelles

• ribosomes

plasma membrane

forms boundary for cell; selectively permeable

what is the plasma membrane made up of?

phospholipids, proteins, carbohydrates

endoplasmic reticulum

network of membranous sacs & tubes; active in membrane synthesis & other synthetic/metabolic processes; has rough & smooth regions

nuclear envelope

double membrane enclosing the nucleus, perforated by pores, continuous with ER

nucleolus

nonmembranous structure involved in production of ribosomes; nucleus has 1 or more of these

chromatin

material consisting of dna & proteins; visible in a dividing cell as individual condensed chromosomes

ribosomes

completes that make proteins; free in cytosol or bounded to rough ER/nuclear envelope

golgi apparatus

organelle active in synthesis, modification, sorting, and secretion of cell products

lysosome

digestive organelle where macromolecules are hydrolyzed

mitochondrion

organelle where cellular respiration occurs & most ATP is generated

central vacuole

prominent organelle in older plant cells; functions include storage, breakdown of waste products, and hydrolysis of macromolecules; enlargement of this is a major mechanisms of plant growth