Cell vs. virus: A battle for health - Shannon Stiles
View full lesson: http://ed.ted.com/lessons/cell-vs-virus-a-battle-for-health-shannon-stiles All living things are made of cells. In the human body, these highly efficient units are protected...
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You're in line at the grocery store when, uh oh, someone sneezes on you. The cold virus is sucked inside your lungs and lands on a cell on your airway lining. Every living thing on Earth is made of cells, from the smallest one-celled bacteria to the giant blue whale to you. Each cell in your body is surrounded by a cell membrane, a thick flexible layer made of fats and proteins, that surrounds and protects the inner components. It's semipermeable, meaning that it lets some thing pass in and out but blocks others. The cell membrane is covered with tiny projections. They all have functions, like helping cells adhere to their neighbors or binding to nutrients the cell will need. Animal and plant cells have cell membranes. Only plant cells hav...
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You're in line at the grocery store when, uh oh, someone sneezes on you. The cold virus is sucked inside your lungs and lands on a cell on your airway lining. Every living thing on Earth is made of cells, from the smallest one-celled bacteria to the giant blue whale to you. Each cell in your body is surrounded by a cell membrane, a thick flexible layer made of fats and proteins, that surrounds and protects the inner components. It's semipermeable, meaning that it lets some thing pass in and out but blocks others. The cell membrane is covered with tiny projections. They all have functions, like helping cells adhere to their neighbors or binding to nutrients the cell will need. Animal and plant cells have cell membranes. Only plant cells hav...
