Cell Biology Outline Organization of body systems Organ

Cell Biology

Outline • Organization of body systems – Organ – Tissue – Cell— • How do we study biology? – Why should we? • Research question in biology

Body System Hierarchy System > Organ > Tissue > Cell

Body System Hierarchy System > Organ > Tissue > Cell Cardiovascular System

Body System Hierarchy System > Organ > Tissue > Cell Cardiovascular System Blood Vessel (Organ) Vessel Tissue

The functional part of organs are cells + matrix System > Organ > Tissue > Cell Blood Vessel Tissue Cells + Matrix are proteins that hold cells together and give tissues mechanical integrity

The functional part of organs are cells + matrix Matrix Example: bone tissue Cells Matrix

The functional part of organs are cells + matrix Matrix Example: bone tissue Cells Blood vessels Matrix

The Cell

The Cell This is not a cell…so what is it? ~3 um 50 um ~100 nm ~6 um ~5 um ~7 um

What can cells do? Adhesion Change Shape (Spread) Cell Matrix Migrate Direction of Migration Communicate Hey Actin Focal Adhesion Hi

How do we study Biology? In vitro In vivo Within glass Within the living

Why do we study Biology? In vitro In vivo If we understand why cells malfunction, we can learn how to fix them

Research Question: What role does matrix stiffness have on cells? Stress Shielding Cancer

Let’s look at an experiment on single cells 50 um 50 x 10 -6 m 1, 000 Pascals 1 k. Pa 50 um 50 x 10 -6 m 10, 000 Pascals 10 k. Pa

Substrate Stiffness Affects Cell Size 50 um Area (um 2) 50 x 10 -6 m 1, 000 Pascals 1 k. Pa Area vs. Stiffness 50 x 10 -6 m 10, 000 Pascals 10 k. Pa 1400 1200 1000 800 600 400 200 1000 2500 5000 Stiffness (Pa) 10000

Cell Proliferation (cell division) Cell Nucleus (DNA)

What’s in cells? Proteins run the show Example: Structural proteins give cells shape

What’s in cells? Proteins run the show Other proteins do lots of other things