Cell Systems and Interactions (Ch 7 and 11)

Bio 1113 at Ohio State

Steps of Secretory Pathway

1. protein enters ER

2. protein exits ER in a vesicle

3. Protein enters cis face of Golgi and gets tagged

4. Protein leaves trans face of Golgi and gets shot out in a vesicle

ER signal sequence

1. Protein & ER sig sequence synthesized.

2. sequence binds to SRP, stops synthesis

3. Moves to rough ER and attaches to SRP receptor

4. SRP is released, protein goes into ER

Parts of the Cytoskeleton

Actin fila, Intermediate fila, Microtubules

Actin Filaments

2 coiled strands, divides anim. cells and moves organelles

Intermediate Filaments

fibers wound into thick cables, anchors nucleus

Microtubules

hollow tube, track for intracell transport

Cellular Movement

Uses Actin & Myosin, pulls

Intracell Transport

uses Microtubes & kinesin, walks

The 4 ways cells are attatched

Tight Junctions, Desmosomes, Gap Junctions, Plasmodesmata

Tight Junctions

stitches, prevent passage

Desmosomes (ANIMAL ONLY)

welds, structural support

Gap Junctions

hollow pins, direct communication

Plasmodesmata (PLANT ONLY)

clothing tags, bridge and plug gaps in cell walls

Lip-Soluble signaling

Reception > Signal Response > Deactivation

Lip-Insol signaling

Reception > Transduction > Response > Deactivation