<p><span style="font-size: 16px;">Actions of viruses on the host cell disrupt homeostasis, whether it is by lysis, or if the cell spends time and energy replicating the virus. </span></p> <p><span style="font-size: 16px;">There are many infectious diseases caused by viruses, the common cold and flu(influenza) are just two examples. </span></p> <p><span style="font-size: 16px;">Read the following pages on How Stuff Works</span></p> <ul> <li><span style="font-size: 16px;"><a href="http://science.howstuffworks.com/life/cellular-microscopic/virus-human2.htm">How a Virus Infects you</a></span></li> <li><span style="font-size: 16px;"><a href="http://science.howstuffworks.com/life/cellular-microscopic/virus-human3.htm">On the inside</a></span></li> <li><span style="font-size: 16px;"><a href="http://science.howstuffworks.com/life/cellular-microscopic/virus-human4.htm">Lysogenic Cycle</a></span></li> <li><span style="font-size: 16px;"><a href="http://science.howstuffworks.com/life/cellular-microscopic/virus-human5.htm">Reducing the Spread</a></span></li> <li><span style="font-size: 16px;"><a href="http://science.howstuffworks.com/life/cellular-microscopic/virus-human6.htm">Medicines that Can Help</a></span></li> </ul> <p><span style="font-size: 16px;">Then watch the video, <a href="https://youtu.be/Rpj0emEGShQ">Flu Attack! How a Virus Invades Your Body</a> </span></p> <p><iframe src="https://www.youtube.com/embed/Rpj0emEGShQ?wmode=opaque" width="560" height="315" frameborder="0" allowfullscreen=""></iframe></p>