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www.denniskunkel.com Tour of the

Today’s Topics • Properties of all cells • Prokaryotes and • Functions of Major Cellular – Information • Nucleus, – Synthesis&Transport • ER, Golgi, Vesicles – Energy Conversion • Mitochondria, – Recycling • , – Structure and Movement • and Motor • Cell Walls 9/16/11 1 www.denniskunkel.com

Bacterial (Prokaryotic) Cell Common features of all cells • Plasma Membrane – defines inside from outside Ribosomes!

Plasma membrane! • Bacterial ! – Semifluid “inside” of the cell !

0.5 !m! • DNA “” Flagella! - Genetic material – hereditary instructions No internal • Ribosomes membranes – “factories” to synthesize proteins 3 4

Figure 6.2b 1 cm

Eukaryotic Cell Frog egg 1 mm

Human egg 100 µm Most and cells 10 m µ Nucleus

Most microscopy Light 1 µm

Super- 100 nm Smallest bacteria Viruses resolution microscopy Ribosomes

10 nm microscopyElectron Proteins Lipids 1 nm Contains internal organelles Small molecules 5 0.1 nm Atoms

1 endoplasmicENDOPLASMIC RETICULUM reticulum (ER) (ER) NUCLEUS NUCLEUS Rough ER Smooth ER nucleus Rough ER Smooth ER Nucleus

Plasma membrane Plasma membrane Centrosome Centrosome

cytoskeletonCYTOSKELETON CYTOSKELETON You should Microfilaments Intermediate filaments know everything Intermediate filaments in Fig 6.9 ribosomesRibosomes Microtubules Ribosomes cytosol GolgiGolgi apparatus apparatus Peroxisome Peroxisome

In animal cells but not plant cells: In animal cells but not plant cells: Lysosome Lysosome Lysosomes Figure 6.9 Figure 6.9 Centrioles Mitochondrion lysosome Flagella (in some plant 7sperm) Mitochondrion Flagella (in some plant 8sperm) mitochondrion

Nuclear envelope Nucleus Ribosomes

Cytosol Nucleus 1 !m ER Free Ribosomes Make Cytoplasmic Proteins

Nuclear envelope: Inner membrane – Carry out synthesis Outer membrane

Pores Membrane Bound Ribosomes Pore Make Proteins complex to be Exported

Rough ER

Surface of nuclear envelope. 1 !m 0.25 !m Large subunit Close-up of nuclear envelope TEM showing ER and ribosomes 0.5 !m Figure 6.10 Small 9 10 Pore complexes (TEM). Nuclear lamina (TEM). subunit Figure 6.11 RNA & Protein Complex Diagram of a ribosome

1 Nucleus ENDOPLASMIC RETICULUM (ER) Nuclear envelope is connected to ER NUCLEUS EndoplasmicRough ER Smooth ER Reticulum Rough ER Plasma membrane Centrosome Smooth ER 2 transport vesicles CYTOSKELETON

Microfilaments Intermediate filaments Golgi Microtubules Ribosomes Ribosomes 3 Golgi pinches off Transport Vesicles, Lysosomes, etc. GolgiGolgi apparatus apparatus Peroxisome

In animal cells but not plant cells: Figure 6.9 Lysosome Lysosomes Figure 6.16 4 5 Plasma6 membrane expands Mitochondrion Centrioles 11 12 Flagella (in some plant ) by fusion of vesicles.

2 Rough ER Smooth ER Has attached ribosomes

• Synthesis of – secreted proteins • Synthesis of – membrane proteins membrane lipids • Synthesizes steroids • Stores calcium • Detoxifies poison

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Golgi Apparatus: protein secretion Processing, packaging and sorting center

Cis Trans Golgi Golgi Adds Close Away oligosaccharides To Rough From ER Rough (glycosylation) ER

15 16

Mitochondria: NUCLEUS Powerhouses of the cell

Mitochondria (and chloroplasts) Food -> ATP

Figure 6.9 17 18

3 Chloroplasts capture ENDOPLASMIC RETICULUM (ER) energy from the sun Rough ER Smooth ER

Chloroplast Photosynthesis

Ribosomes Stroma Inner and outer DNA membranes

Granum

1 !m Peroxisome

Thylakoid Sunlight -> ATP, Sugar Figure 6.9 Lysosome 19 Lysosome ( only) 20

Microtubules Microfilaments Intermediate ENDOPLASMIC RETICULUM (ER) Filaments Actin NUCLEUS various 25 mM dia 7 mM dia Rough ER Smooth ER There are three 8-15 mM dia types of fibers that Cell shape Cell shape Nuclear movt Cell lamina make up the Chromosome Cytoplasmic Tension separation streaming bearing CytoskeletonCYTOSKELETON cytoskeleton Flagellar mvt Muscle contract elements Microfilaments Anchors Intermediate filaments Motors: Motors: Microtubules Myosin Kinesin Cytosol

Figure 6.9 21 22

Table 6.1

Movement of Vesicles along Microtubules

Vesicle ATP Receptor for motor protein

Motor protein (ATP powered) of cytoskeleton (a) Motor proteins that attach to receptors on organelles can “walk” the organelles along microtubules or, in some cases, microfilaments. Microtubule Vesicles 0.25 !m

What evidence do we have that they actually move?

(b) Vesicles containing neurotransmitters migrate to the tips of nerve cell axons via the mechanism in (a). In this SEM of a squid giant axon, two vesicles can be seen moving along a microtubule. (A separate part of the Figure 6.21 A, B experiment provided the evidence that they were in fact moving.) 23 24

4 Motor MAPs transport vesicles Three kinds of Movement

• Filament anchored: motor “walks” along filament (transport vesicles) Dynein inbound • Motor anchored: filament moves (muscles)

• Both anchored: bending (cilia and flagella) outbound MTOC kinesin

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Fig. 6-24 Ribosomes (small brown dots) Outer microtubule Plasma 0.1 !m! doublet! membrane! Rough Dynein proteins! have 2 other supportendoplasmic reticulum Smooth mechanismsNUCLEUS endoplasmic Central reticulum microtubules! Golgi apparatus Microtubules! Central /Tonoplast (b)!Cross section of • Cell Wall Plasma ! membrane! ! • Vacuole or Microfilaments Intermediate CYTOSKELETON Tonoplast filaments 0.5 !m ! Microtubules (a)!Longitudinal 0.1 !m! section of cilium Mitochondrion ! Triplet! Cilia and Flagella Peroxisome Have 9+2 arrangement of microtubules Plasma membrane Chloroplast and motor proteins. Cell wall Wall of adjacent cell Plasmodesmata Figure 6.9 (c) Cross section of basal body! 27 28

Central (Tonoplasts) Extra Cellular Matrix – Only in plants

glycoproteins

Central vacuole

Cytosol

Acts like a “balloon in a box” to hold plant cells Tonoplast Nucleus Central rigid vacuole

Cell wall

Chloroplast Figure 6.15 29 30 5 !m

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