AP Biology Unit 2 - Cellular Organelles

Nucleus Structure

Double membrane (nuclear envelop)

Nucleus Function

Store genetic information (DNA), synthesis of RNA, ribosome subunit assembly

Rough ER Structure

Membrane studded with ribosomes attached to nuclear envelope

Rough ER Functions

Site of membrane-bound protein and secreted protein synthesis, cell compartmentalization, mechanical support, role in intracellular transport

Smooth ER Structure

Folded, tubelike structure (cisternae)

Smooth ER Function

Detoxification, calcium storage, lipid synthesis

Mitochondria Structure

Double membrane; outer is smooth, inner is highly folded

Mitochondria Function

site of oxidative phosphorylation, site of Krebs Cycle (matrix)

Chloroplast Structure

Double outer membrane (grana stacked and fluid stroma)

Chloroplast Function

Site of photosynthesis, thylakoid light reactions, stroma Calvin-Benson Cycle

Golgi Complex Structure

Membrane-bound structure composed on flattened sacs (cisternae)

Golgi Complex Function

Folding and chemical modification of synthesized proteins, packaging protein traffic

Ribosomes Structure

Composed of rRNA and protein, large and small subunits, bound or free types

Ribosome Function

Protein Synthesis

Vacuole Structure

Membrane-bound sac

Vacuole Function

Storage and release of macromolecules and cellular waste products, water retention (turgor pressure), osmoregulation (protist), fuse with lysosome

Lysosome Structure

Membrane-closed sacs that contain hydrolytic enzymes

Lysosome Function

Intracellular digestion; recycling and apoptosis (programmed cell death)