Prokaryotic celllack membranebound organelles Eukaryotic Cellcontain membranebound organelles

Prokaryotic cell—lack membrane-bound organelles

Eukaryotic Cell—contain membrane-bound organelles (plants, fungi, animals, humans)

Plant and Animal Cell

Chromatin Nuclear envelope Nucleus Nucleolus Plasma membrane Smooth endoplasmic reticulum Cytosol Lysosome Mitochondrion Centrioles Rough endoplasmic reticulum Ribosomes Centrosome matrix Golgi apparatus Microvilli Secretion being released from cell by exocytosis Microfilament Microtubule Intermediate filaments Peroxisome Figure 3. 2

Cell organelles • Nucleus—contains DNA, RNA • Central Dogma—DNA codes for RNA and RNA codes for proteins • Ribosomes on ER to make proteins • Smooth ER where lipids are made • Liver cells have lots of smooth ER • Proteins exit ER in vesicles. Lipids don’t need vesicles • Protein vesicles go to Golgi apparatus—processed, sugars added, folded, tagged for delivery

Nucleus & Rough ER

Production of a Protein Cytosol Transport vesicle budding off Coatomercoated transport vesicle 5 Ribosomes m. RNA 3 4 Sugar group 2 1 Released glycoprotein Signal Receptor sequence site Signalrecognition particle (SRP) ER membrane Growing polypeptide Signal sequence removed ER cisterna

Ribosome reading RNA to make protein

Ribosomes on Endoplasmic Reticulum • Granules containing protein and r. RNA • Site of protein synthesis

Figure 3. 38

Smooth ER

Golgi Apparatus