See, Its like this.
1) The FS is handed over to both Dev team and the QA Team
2) The PM / PL would have set delivery dates for Dev/QA and 
Client.
2.a) Dev Team by the delivery date gives some modules which 
are developed
2.b) QA Team by the delievery date Tests the Application , 
Finds bugs and Retests Fixed bugs
2.c) Once the Exit Criteria is Met ( set by PM / PL ) , the 
code is delivered to the client.
2.d) Client May give to its QA ( Called SQA ) or the UAT 
Team
3) This is repeated for each Iteration ( There can be 4 
iterations for 15 Month Project )
4) The above procedure is done if the project is Medium / 
Complex ( Say 7-8 Months and above )
5) For Simple Project the whole procedure is done in 1 shot.

Well dear,
1. After receiving requirments developer as well tester 
need to understad the application which client needed.
2. While In design phase TL (generally) needs to prepare 
Test Strategy and Test plan.
3. While coding phase.Test real work starts say writing 
test cases preparing test data. Preparing QTP and WinRunner 
script as needed basis.
4. While in Testing phase: Execution of test cases and 
preparing test reports.
After completion of testing delevory to the client. Where 
Client will do the UAT and finally accpt.........

Which completes the project developement.
:)