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.

An ocean food web

An Ocean Food Web Cytoscape network model 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 Phone Network

Cell Phone Network 1A Jasmine 1D Josh 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 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 node 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 Network 1.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.