H O W A R E C E L L S L I N K E D T O O N E A N O T H E R ?

D E C E M B E R 2 0 , 2 0 1 3

R E M I N D E R S

• Pick up HW 7 Before you leave

• Character Surveys

• Test Corrections

• Do something exciting over break

• Learn a new skill, like juggling

• Defeat your arch nemesis

• Climb a mountain

A G E N D A

• Review of Cytoskeleton

• Extracellular matrix

• Exit Slip and Summary

• Lab Clean Up

M I C R O T U B U L E S

• Hollow rods made of tubulin

• Tubulin is a dimer (alpha and beta tubulin)

• Tracks for motor proteins

• Attach to chromosomes during mitosis

M I C R O T U B U L E O R G A N I Z AT I O N• Centrosome - base for microtubules to attach to

• Centrioles - nine triplets of microtubules in a ring that help organize microtubules

• Centrioles and Centrosomes are important in cell division

C I L I A A N D F L A G E L L A

M I C R O F I L A M E N T S

• Thin, solid rods built from the protein actin

• Branching filaments

• Bears tension

• Maintain cell shape

I N T E R M E D I AT E F I L A M E N T S

• More permanent than microtubules and microfilaments

• Bears tension, maintains shape

C E L L W A L L• Found in Plant Cells

• Hold plants up against gravity

• Composed of Cellulose, proteins, and polysaccharides

E X T R A C E L L U L A R M AT R I X

• Found in Animal Cells

• Glycoproteins (protein covalently bonded to carbohydrate) and other Carbohydrate-containing molecules

E X T R A C E L L U L A R M AT R I X

• Collagen is major glycoprotein

• Binds with proteoglycans - small protein with many carbohydrates

• Cells attach to the ECM (collagen and proteoglycans) by binding to fibronectin

• Fibronectin can the bind to integrins, or proteins integrated in the plasma membrane of a cell

C E L L J U N C T I O N S - P L A N T• Plasmodesmata

• Plant cell junctions that cross between cell walls

• Water and small solutes pass freely

C E L L J U N C T I O N S - A N I M A L

• Tight Junctions - forms seal around the cell

• Desmosomes - Link cells together in sheets. Intermediate filaments anchor desmosomes in cytoplasm.

• Gap Junctions - similar to plasmodesmata, provide a link between animal cells. Important for cell-cell communication and sending signals.

R E D L I G H T• In your notebook, explain the function for each of the following.

You may not use your notes!

• Nucleus

• ER (Smooth and Rough)

• Golgi

• Nuclear Envelope

• Ribosome

• Cell Wall

• Mitochondria

• Chloroplast