Warm-up – 09/13

• Pass in your syllabus if it is signed

In your warm-up section of your binder:

1. Describe what the word “network” means to you.

2. What examples of networks can you think of? (It’s okay if your examples are not related to Biology.)

An Introduction to Networks in Biology

September 13, 2004

Networks in Biology

Network =

an interconnected or interrelated chain, group, or system.

http://staff.harrisonburg.k12.va.us/~gharper/bay/weboflifepage/foodweb.jpg

An ocean food web

An Ocean Food Web

Cytoscape networkmodel of food web

Network terminology

Nodes- members of the network

Edges- the relationships between the nodes

What do the nodes represent?What do the edges represent?

Creating our own Cell PhoneNetwork

Cell Phone Network

1AJasmine

1DJosh

can call

•Today we will create a diagram of a cell phone network, showing who can call who in our classroom

•The nodes in this network are students, and the edges are arrows showing who can call whom

•We will be able to use this diagram to track the flow of information throughout the classroom

node node

edge

Cell Phone Network• The direction of the arrow is important in many

networks. • In the example below, the single arrow pointing

from 2A to 3A tells us that 2A can call 3A– Notice that 3A cannot call 2A back, since

there is no arrow pointing in that direction

nodenode

nodenode

edge edge

edge

edge edge

edge

Cell Phone Network

• How many people can 1A call?

• How many people can call 1A?

• How many people can call 4A

• If 2A hears a juicy rumor, who else will find out about it?

Rules for this Network

• Your phone book is full, you cannot add or delete names from it

• You have no caller ID, so you can’t necessarily call back someone who has called you

• If your friends want to know who you can call, they need to ask you and you can tell them verbally

Mapping the Network1. Fill in the names of everyone in your phone book. You’ll

probably need to move around the room!

2. Meet in groups with everyone who shares the same number as you and draw as much of the network as possible on the provided butcher paper (for example, if your phone is 3E you will meet with all the 3’s)

3. Split up and meet in small groups with everyone who shares the same letter as you, and collect information from those other groups (on provided paper)

3. Meet back with all those who share the same number as you, and complete your network drawing on the butcher paper

4. Complete the “Introduction to Networks” questions.