Big Questions What is LIFE? How can we tell things that are alive from things that were alive or were never alive?

OBSERVING LIFE and NONLIFE We now need to practice making observations of things and determining if they are alive, once alive, or never alive. This activity will allow you to practice writing CAREFUL and THOROUGH descriptions of what you see.

Life or Nonlife? Watch the short video clip of the Rover “Spirit” which is explored the planet Mars.video clip

Life or Nonlife? Imagine that you have two soil samples from somewhere on Earth. Your job is to examine them, write a complete description of the objects you see, and determine whether objects are ALIVE, ONCE ALIVE or NEVER ALIVE

Observing soil samples I will place soil samples on your desk: today you will examine soil from a DESERT. Observe a part of each sample in a half Petri dish Use a microscope and a magnifying glass.

Observing soil samples Each person should write careful descriptions of soil samples Use as many adjectives as you can Describe size, shape, color of particles Explain WHY you think each object you see is alive, once alive or never alive

Observing soil samples You will be able to add to your observations tomorrow. TODAY before you leave, please add clean spring water (with no chlorine) to the DESERT SOIL only. Add water until the cup is half full. Water sometimes activates dormant living things.

Soil samples: Day Two Observe forest soil and desert soil again, adding to your descriptions of the objects you see in the soil. Make small drawings of any objects you see in the soil. Make note of any changes you see in the samples today. (Use a pipette to add a few drops of desert water to the Petri dish, so you can look at it under the microscope Then you will turn in your written observations on Friday.