Exam 2 Flashcards
Cell membrane
separates intracellular & extracellular environments; mediates
interactions with extracellular environment & with other cells
Nucleus
directs most protein synthesis & almost all nucleic acid synthesis
Nuclear envelope
separates nucleus & cytoplasm, mediates transport between them
Nucleolus
(within nucleus) rRNA synthesis; assemble of ribosomal subunits
Cytosol
liquid matrix surrounding cytoplasmic organelles; site of many
metabolic reactions; osmoregulation; synthesis of proteins that the cell
will NOT secrete
Ribosomes
translation of mRNA into proteins (protein synthesis)
Rough ER
modification & folding of proteins synthesized on ribosomes;
synthesis proteins that will be packaged in membranes & transported
within the cell (i.e. proteins destined for secretion, lysosomal
enzymes, membrane proteins)
Smooth ER
synthesis of fatty acids, phospholipids, & steroid hormones; Ca2+
storage (skeletal & cardiac muscle); drug detoxification (liver)
Mitochondria
energy production (mainly ATP); often initiates apoptosis
Golgi Apparatus
final assembly and modification of membrane-packaged proteins
synthesized in the RER; protein sorting & dispatch to their ultimate
destination; membrane recycling
Endosomes
endocytosis; sorting of endocytosed materials to determine
intracellular destination; storage before destruction in lysosome
Phagosomes
phagocytosis (form of endocytosis); storage & transport of
phagocytosed materials; destruction of endocytosed materials (usually
by merging with lysosomes)
Vesicles and granules
transport materials between different organelles & to/from cell
membrane; storage of materials that are to be exocytosed
Lysosomes
degradation of waste products; killing pathogenic organisms;
digestion of hormone secretory vesicles
Peroxisomes
synthesis of H2O2 (used for killing pathogens) bile (liver),
plasmalogen, & cholesterol; detox of some materials (including
ethanol); degradation of long chain fatty acids via β-oxidation
