chapter 4 plasma membrane, nucleus and ribosomes
TRANSCRIPT
What to Know
• The structure and function of the plasma membrane, nucleus and ribosomes.
Figure 4.5
0.1 m
(a) TEM of a plasmamembraneOutside of cell
(b) Structure of the plasma membrane
Insideof cell
Hydrophilicregion
Hydrophilicregion
Hydrophobicregion
Carbohydrate side chains
Phospholipid Proteins
Plasma Membrane
Concept 4.3: The eukaryotic cell’s genetic instructions are housed in the nucleus and carried
out by the ribosomes
• The nucleus contains most of the DNA in a eukaryotic cell.
• Ribosomes use the information from the DNA to make proteins.
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Ribosome
Chromatin
Rough ER
Nucleus
Nucleolus
Chromatin
Nuclear envelope:
Nuclear pore
Inner membraneOuter membrane
Porecomplex
Close-upof nuclearenvelope
Nucleus
Ribosomes: Protein Factories
• Ribosomes are complexes of ribosomal RNA and protein.
• Ribosomes carry out protein synthesis in two locations– In the cytosol (free ribosomes)– On the outside of the endoplasmic reticulum or the
nuclear envelope (bound ribosomes)
© 2014 Pearson Education, Inc.
Figure 4.9
TEM showing ER and ribosomes Diagram of a ribosome
Ribosomes bound to ER
Free ribosomes in cytosol
Endoplasmic reticulum (ER)
RibosomesER
0.25 m
Largesubunit
Smallsubunit
Figure 4.7b
CYTO-SKELETON
NUCLEUS
Smooth endoplasmicreticulum
Chloroplast
Central vacuole
MicrofilamentsIntermediatefilaments
Cell wall
Microtubules
Mitochondrion
Peroxisome
Golgiapparatus
Plasmodesmata
Plasma membrane
Ribosomes
NucleolusNuclear envelope
Chromatin
Wall of adjacent cell
Rough endoplasmicreticulum
You should be familiar with the parts of a cell.
1 m
Nuclear envelope:Inner membraneOuter membrane
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